Which composers are you a fan of to the point where you actually purchase (as in actually pay $$$, not download) their cds?
I've been a fan of various composers in the past (mostly game), but most have basically retired (Uematsu) or become jobless (Hirota). These days I'm a fan of:
Shoji Meguro (Shin Megami Tensei and spinoffs) - Always been impressed by how Meguro could take on various genre (jazz, metal, rock, electronic) while still maintaining the SMT feel in every one. The guy's been making music for quite a while now and doesn't seem to be losing his edge as the P3 soundtrack showed.
Takeharu Ishimoto (World Ends with You, Crisis Core, soon Dissidia, then FFXIII Agito) - The best upcoming game composer IMO. He came out of nowhere last year with two extremely different soundtracks that were both game soundtrack of the year worthy. Judging by his FF7 mixes in Crisis Core, his new mixes of songs from FF1-10 in Dissidia should be pretty freaking awesome.
Naoki Satou (X, Eureka Seven, Sword of the Stranger) - I didn't even know Satou did all these soundtracks when I first bought them separately because they were such great compositions. Later on when I learned that I already owned most of this guy's major compositions I realized how amazing of a composer he is and so now I'm a fan.
Those are pretty much the only composers I'm happy with 100% of the time anymore. There are a lot of composers that do good stuff/bad stuff but those 3 are pretty darn consistent. I would put Yasunori Mitsuda as he's my favorite composer but he makes a lot of just above average stuff in between the rare releases of a major AAA soundtrack like Xenogears, Chrono Cross, Xenosaga, Soma Bringer.