What I did was wait until Penny's had their 50% off sale. It's not top of the line quality, but my suit looks very nice even after I've worn it. I just take it to the dry cleaners every couple times.
Watch out for what the suits are made of. Poly Blends and synthetic materials will get a shine to them as they are worn. This makes them look cheap and won't last as long. Many places like Younkers and JC Pennys are blended materials. I would advise you yo buy a wool suit or something with a high wool percentage in it.