Without a doubt, the kings of my collection are none other than Sparks. Closely followed by the Carpenters (7 records). (A click on the "record collection" link in my sig will lead you to the cold hard truth.)
I've managed to collect 16 of their 22 albums on vinyl (though I don't really think I'll be buying the vinyl cut for "The Seduction of Ingmar Bergman" no matter how much I want to contribute to their low revenue). Two of those albums I have doubles of (because one is on red vinyl, and the other is only there because of a purchase mistake, bwaha). I also have 13 12" singles (despite the fact that there are a few others that I really want but my pocketbook suffers lately) two of them being coloured vinyl.
Most of my Sparks records (including the 12" singles) have been imported from the UK and Germany. (And let me tell you, the exchange rate is freaking awful.) My most expensive record is my yellow 12" "Beat the Clock", which, to my memory, was almost 40 US dollars.
I also have the rare "Profile" collection (2 discs, CD format) and 1 of their 3 DVDs released (live footage from London, 2000/01) - however I'm hoping to snag another one of these days! Most of the MP3's I've purchased legally have been (aye, you guessed it) also Sparks. So basically I'm always Sparkin'.
If you take a gander at Alocer's
CRF Cribs thread you'll see that Sparks have also taken over my tiny little bedroom! (And that's nothing compared to the Sparks buttons I have.)
So yeah. It's safe to say that my collection has been outnumbered by the Mael persuasion.