You can try the games voted here: http://forums.toucharcade.com/showthread.php?t=21410 So far there are voting results for 4 genres.
Inkvaders, iMech, Catch Cows, Aqua Globs, Fling!, Minigore, Doodle Jump, Battle Bears, Cowabunga Full, Moon Drop, My Brute, Paper Toss World Tour, Alive 4 ever, Stacked. That should keep you going
Minigore, StoneLoops! of Jurassica, Bloons, Alive 4-ever. Edit* Just bought Rise of empires and it's a good game! Also for $.99.
I found inkvaders a bit too hard for a casual gamer like myself and once you have had one really good go at it and got the best guns then it's boring to go back and start again with the lame guns
One game I see that doesn't get much love is G.I. Joyride. It's a very laid back type game that you can just kick on and enjoy. I probably play it more then anything else. Just got Textropolis which is also very relaxing just kinda play at your own pace and enjoy it type game. If you want anything a little more hardcore there are a lot of cheap Gameloft games like hero of sparta, and castle of magic. Oh yeah and Sky Burger and Scoops are fun .
I play this one a lot more than I probably should. Not a whole lot of game, but what is there is fun!
The answer to the "best $0.99 and $1.99 games" is any game that used to cost more money. Preferably a game that's done a "peggle" and moved from $4.99 to $0.99. It makes you feel good for saving money, and most games that used to cost more, are usually better especially if they're in the top 50.
Sorry took so long to reply Yeah, i have Zombieville and Mummy's Revenge and Inkvaders blows them both out of the water. Loads of updates are coming and it is an amazing game.