You didn't specify, but I'm going to guess you want something for micing up your amp, not recording acoustic. If this is the case then I'd say your only real option is a dynamic cardioid, SM57. You'll ruin a condenser by sticking it next to your amp, plus you'll struggle to get a decent sound IMO. Condensers tend to boost the high frequencies and this doesn't flatter distorted guitar sounds. There's a reason why everyone uses Shure Mics, they're so good. They've blown everything else I've ever used away. Plus they're so versatile you can use them for almost anything else. If you ask specific questions about mics then I might be able to answer them. I don't want to patronise you though by telling you a load of stuff you already know. HopeI've helped.
Ben