When writing a sentance of dialog, the stuff in between the quotation marks, is what the character is saying; the stuff that falls outside of the quotation marks, is called a 'speech tag.'
The most common form of speech tag is a word identifying the person speaking, and then 'said': he said, she said, Samantha said, Tommy said. 'Said' is used so often that people don't really register it. It becomes almost an invisible word -- going to great lengths to avoid using it is a mistake. But using it as your only speech tag isn't very wise either; it limits your rhythm patterns, and there are many other ways to convey the same information more vibrantly.
The first way is to use some other word in place of said. Many people in publishing are willing to say contemptuous things about 'said-isms', but every author I know uses them. The trick is to never force the issue. If the most natural word to use is 'said', use 'said'. But what if they didn't just 'say' it? If another word fits the way the character delivered the dialog better, feel free to use that word instead.
Viola turned away from him, gazing down the track towards Kinnyon Manor.
'You're not going there!' he said.
To me, the 'said' feels out of place after the exclaimation mark. If there is enough force in the words that the exclaimation point is merited, then there is enough expression in the tone that a plain vanilla 'said' not longer seems appropriate. Furthermore, there is so little contextual information that from this snippet you can deduce nothing about these characters, or their situation.
Viola turned away from him, gazing down the track towards Kinnyon Manor.
'You're not going there!' he exclaimed.
I have met at least one person who claims that using 'exclaimed' in this situation is redundant, but then, so is 'said' redundant. You knew someone was speaking as soon as you hit the opening quote. I think it feels better to have no conflicting evidence between the punctuation and the speech tag. Unfortunately, in this version there is still very little contextual information. We can guess, perhaps, that there is something wrong with Kinnyon Manor, but we have no idea what. Look what happens when we replace the word 'exclaimed' with something a little more specific and evocative.
Viola turned away from him, gazing down the track towards Kinnyon Manor.
'You're not going there!' he commanded.
Now we have a situation with some interest -- tension... conflict, even.
Viola turned away from him, gazing down the track towards Kinnyon Manor.
'You're not going there!' he whined.
And with one word we turn the encounter entirely on its head.
Viola turned away from him, gazing down the track towards Kinnyon Manor.
'You're not going there!' he sneered.
And now we have a new situation once again.
Funny how much effect these despised said-isms can have. You see why it would be silly to forbid their use.
But if evey time someone says things you come out with a new and different said-ism, then your readers are going to get tired of it, since the more unusual the word, the more it draws attention to itself. They will want to be paying attention to the story, not the speech tags.
Since 'said' conveys very little information, and 'said-isms' are to be used sparingly, how else are you supposed to dress up your dialog? Oddly enough, one of the mostly highly reccomended ways to do speech tags... is to not use speech tags.
If you are really skilled at making your character's speech patterns distinct, you can have a few exchanges in a row, with nothing there at all except for what is between the quotation marks. But the usual way to indicate the speaker without the use of speech tags, is to interspace the spoken lines with character action, or description. Not only does this identify the speakers, it also allows you to break up the flow of verbal information with some visual and kinesthetic input, making the conversation seem more dynamic and alive. Visually oriented readers tend to get bored quickly whenever your story diminishes itself into 'talking heads'.
The convention is that each speaker must get their own paragraph. So when you depict only one character outside the quotation marks in that same paragraph, that must be the one who is doing the talking.
Viola turned away from him, gazing down the track towards Kinnyon Manor.
He touched her arm. 'You're not going there!'
This conveys almost exactly the same information that 'he said' did earlier, we know who is talking, but that's about it.
Viola turned away from him, gazing down the track towards Kinnyon Manor.
He grabbed her arm. 'You're not going there!'
This works about the same as exclaimed or commanded.
Viola turned away from him, gazing down the track towards Kinnyon Manor.
He pawed ineffectually at her arm. 'You're not going there!'
And this does a pretty good job of substituting for the whine.
Instead of adding actions, it is perfectly allowable to describe other things, as long as the paragraph focuses on the speaking character -- a description of facial expressions works very well. You can even describe the tone of voice used.
Viola turned away from him, gazing down the track towards Kinnyon Manor.
'You're not going there!' His words came out in a horrified whisper.
Viola turned away from him, gazing down the track towards Kinnyon Manor.
'You're not going there!' His voice boomed like a Sargent Major's as he issued the command.
This particular effect (describing the tone of voice, instead of just identifying it) tends to be a little more florid than using said-isms. It works very nicely when you want the reader to stop and pay attention, but less well when you are aiming for speed.
The last thing you can to do is modify 'said' using adverbs: 'He said coldly', 'he said enthusiastically', 'he said snidely' and so forth.
Viola turned away from him, gazing down the track towards Kinnyon Manor.
'You're not going there!' he said contemptuously.
Using adverbs to modify a weak verb generally doesn't have as powerful an effect as using a nice good strong verb in the first place. Sometimes that's all to the good, but, except in the most unusual circomstances, this should probably be the least common speech tag technique you use.
Use caution in adding adverbs to 'said'. Be careful not to over do it, but most especially you want to make sure that your modifying adverb does not end up acting as a humorous comentary on the speech itself. This form of humor is called a 'Tom Swifty', and although very amusing in the proper setting, tends to be a bit disconcerting when encountered unexpectedly, and incongrously, in the middle of an otherwise serious bit of dialog.
'You're not going there!' he said guardedly.
'Then take me home,' she said domestically.
'I can't, I have twisted my ankle,' he said lamely.
'Then I'll go home without you,' she said abandonedly.
Remember, above all else, that the important thing about speech tags is not to decide on the one true way of doing them and to always use that method. You should master a variety of methods and use them appropriately. Since there are so many different ways to convey the same information, choosing which speech tag method to use frequently depends on the rhythm and flow of your prose. Use the one that sounds and feels best, reading the passage aloud to double-check if you are uncertain.