Any amp you buy will have line level inputs, but it may not have speaker level inputs

You are only installing a sub. Given that, you don't really have any concern about frequency response etc, so you should get whatever you can find locally. If you have a Circuit City, Best Buy, or Radio Shack they all carry them and they will all be adequate for your needs. Crutchfield also sells them.

If you were installing an SQ competition system I might point you toward a Soundgate or something a bit higher end, but frankly, you'd be wasting your money.

d-