There really is no best amp, just what amp is best for you, which takes into consideration what types of music you like, how loud you like to listen, what type of sound do you prefer i.e bright/dark, punchy/laid-back. I personally like the SR-71 because its laid-back and slightly dark yet detailed. Check out Head-fi.org for some opinions and you can get a general consenus on the characteristics of each amp and choose one to start with. Usually what happens is your may not be 100% satisfied, so you buy something else, usually used as Head-fi has a very active classified section, and then you have a playoff, and you end up selling the loser and putting the winner up against some other new competition. Its a vicious cycle, but there are very few ways of getting to try unless you buy, other than head-fi meets, which are gatherings in various cities that happen a couple of times a year per city. Here you can sample many different products and make more informed choices and eliminate some of the field. As far as cables go, get an amp first, the cables can only improve things so much, around the 2% area. Now head over to Head-fi.org, you've got a lot of reading to do.
P.S. Check out Norm Dalgarno's Go-Vibe V3 amp, for $69usd, it may be all the amp you ever need. I bought that amp as my first and I will never get rid of it because it performs 98% as well as amps costing several times as much and its smaller than a deck of cards. You can roll opamps too, (like tube rolling) which can tailor the amp to the sound you prefer to some degree. Again, read about it at Head-fi.
P.S. Check out Norm Dalgarno's Go-Vibe V3 amp, for $69usd, it may be all the amp you ever need. I bought that amp as my first and I will never get rid of it because it performs 98% as well as amps costing several times as much and its smaller than a deck of cards. You can roll opamps too, (like tube rolling) which can tailor the amp to the sound you prefer to some degree. Again, read about it at Head-fi.