Here's a list of some good Pokemon and some info.
Riolu-Unless you use it right or get lucky with types, it won't last long. But Poison Jab is useful for getting certain Pokemon, so if you can't find anything better, use it.
Lombre-Only use it if it knows Water Pulse (not Water Sport). The main reason is Fake Out, which works best with the Double-Battle setting.
Combusken-Only use it if it knows a fire attacking-move and a fighting attacking-move (except Rock Smash). Bulk-Up is nice, but it might not last that long...
Gible and Gabite-ONLY if they know Dragon Rage, and EVERY TIME you see that they do. Don't use anything else, even Sand-Tomb on a Fire-Type! It won't do much anyways. Just Dragon Rage all the way.
Grovyle-Its uses are situational. While it boasts good speed and nifty Grass moves, it won't last long if at all. Personally, I've never been able to keep it in battle for more than a turn or two, but Dusty (the leader) owned me with it, so apparently it can work out.
Vigoroth-ONLY if it's got Body Slam and good ATTACKS. Body Slam's Paralyzing chance helps out a lot and does tons of damage. Brick Break is nice too if you can get it.
Spinda-Kinda odd, I know, but it can prove useful. Water Pulse is good, Teeter Dance is useful, and ifthere's not that much for options you might consider it.
