Leaving mic's aside for the moment the first thing I would suggest when recording tabla is getting a good sound in the room that you're recording in. Recording studio's tend to be quite dead so I'd try to liven the surroundings up by introducing some hard surfaces. Try moving closer to the walls (or even a corner) and maybe putting a sheet of hardboard under you when you're playing to increase the high frequency reflections. If you get a good sound in the room then you'll get a better sound when you record. We record in a room with a wooden floor and fairly bare walls which gives a lovely sound on tablas.
Basically the best mic to use would be a large diaphram condesor mic (not an SM57 or 58 which are both dynamic mic's). Depending on how much recording you're looking at doing then you may be better off hiring a good mic than buying one. If you want a great budget condensor mic then have a look at the Audio Technica AT4033, they're generally around �200-250 and they have a great sound, also worth checking out is the AKG C414 which is a bit more expensive. The Rodes NT2 is also pretty good and only about �300 (not sure if I'd buy that over a AT4033 though).
Bear in mind that you will need a mixer supplying phantom power if you're going to run a condensor mic.