Replying to WTB: Canon 50mm f/1.8

It's the best lens I can afford right now, and even though its only $100 on Amazon I'm looking for something used and cheaper, figured I'd ask here first. This will be for my canon T1i.

I have a 28-105mm f/3.5-4.5 I use as an everyday lens, but I'm not completely stoked on the sharpness. If you could maybe suggest another cheap and sharp lens, let me know. I'm still learning. I'd also like something wide-angle but I'm aware they are expensive and because my camera isn't a full frame it won't be as useful.

Pretty much, I like my lens now but want something else thats sharp! If theres something for like $200ish or under, let me know...Sorry, I'm still learning so if I came across as a noob, don't get heated.

Let me know!