Are there any good words for raising one's voice happily? I only know words such as; roar, shout, bellow, growl... makes you realise how grim my stories really are.
Roar and bellow could both be cheerful, but usually I'd just use some kind of body language, and in context it should be obvious the character's happy. Like... "She finally found a good man!" Jamie said with a smack on his knee. Hmmm... do you necessarily need any kind of dialogue tag? Even my example above, on hindsight, feels like the body language itself wasn't even necessary. It's obvious from the content of the speech and the exclamation mark that it's 1. happy and 2. spoken loudly.
Call, shout, and yell, are pretty neutral, I think - same for roar and bellow. Depends on your context. I'd also say that growling is actually the opposite of raising your voice, but that's probably beside the point. You can whoop and holler if, like me, you're a hick
Hehe, 'cheer' actually slipped my mind. I suppose one can use cry as well. She threw herself in the middle of the crowd and cried. "Party!"
...and declared. "Party!" –what do you reckon? 'acclaim' and 'exclaim' are a couple more to have in the bank for loud snappy scenes.