Androgenic alopecia (and some body hair growth) is caused by a very specific hormone, dihydrotestosterone, (sp?) which is converted in your body from testosterone. Antiandrogens like spironolactone and Androcur inhibit the way your body absorbs testosterone, allowing feminization. After awhile, because your testes aren't being stimulated my T, it slows down production of it. Unfortunately, your body will still convert some of the T that remains so, unless you address your hair loss specifically, HRT won't do lots for it. HRT should arrest head hair loss but won't do much to regrow what's already gone.
Finasteride (Propecia), however, might help... It inhibits the conversion of T to DHT. From the inside out, hair follicles are no longer being effected by DHT; follicles that are still "alive" but made dormant might wake up and grow again. Finasteride also has a lessening effect on body hair for some people. The key is that hair restoration meds only work on hair follicles that have only more recently stopped producing hair. How recently depends on the individual.
Minoxodil (Rogaine) might wake up follicles that are still alive from the outside. The effects of the drug are reported to be increased by concurrent application of tretinoin, a topical medication used to fight acne. The big drawback is that the effects will be maintained only as long as you use it... The hair you got back will probably fall out after you stop using minoxodil. It's also only indicated for crown loss, not the receding part.
I was on HRT for 2 1/2 years when I started using finasteride. I was still kinda hairy (it runs in my family) and my hairline hadn't changed at all. I took it for a year and regained about 3/4" of hairline on my temples and lost almost all of the yucky body hair. My results may be atypical (I think my whole family is androgen senstitive cuz right now, my older sister is hairier than me, lol) but I think finasteride is worth a try.
I hope this helps :-)