I also agree with haymes, before just jumping on the drugs, such as propecia/finasteride try topicals, such as spironolactone, Tricomin etc.. as there can be some pretty serious side effects with propecia/finasteride that you may not be aware of.
I have been using a minoxidil/Sprio/Nizoral regimen for about 3-4 months now and am pleased with the results.
I would say start on Nizoral, then depending on what you are trying to acheive, ie; regrowth or maintenaince, then we can decide on what path to take. minoxidil is only good if you need to regrow hairs.
Have a look on the pages of this site, lots of useful information that should give you the right answers.