How do you sort your LPs?

LP's?  What are those?   <g>  Actually, when I first moved to AZ and needed money, I left my stereo but brought all my albums. I sold them at a swap meet in Tucson for $1200 lump sum. Boy was that a mistake. I'd always open the album, throw the paper liner away and replace it with a plastic lined liner, and the opening was always 90 degrees to the cardboad liner, and NEVER EVER touch the grooves. 

I have over 3500 LPs at this point. I occasionally find duplicates and forgotten music. A less random arrangement would likely be better. It is fun to rediscover music though. 

I really can't imagine any practice other than basic alphabetical filing. Yes, I have a separate section for classical, and also for greatest hits collections that include multiple artists. (I collect radio station greatest hits collections. Please don't ask why.)

My LP collection is large enough that it has to be spread over two floors. So for convenience, it is filed A through Z on each floor. And in my listening room, I have a small "hot box" in the rack to file new purchases as well as current favorites, so that they don't have to be constantly refiled.

Of course, whatever works for you is what's best!

By genre then last name alphanumeric. I'm just starting to try the discog thing. Thanks uber and big greg for the tips, nice.

I have 25,000 LPs, 7,000 78s and 7,000 CDs.  My CDs and LPs are organized by genre, alphabetically and by vocalists/instrumentalists.  There are many genres.  I have excluded Direct to Disc and Japanese 45 rpm/DD LPs onto a separate shelf.  I also have 5,000+ LPs not in the collection with 1/2 sorted by genre, alphabetically and others just by genre.  As to CDs, the large boxed sets are nearly all Classical and located in two rows on top of 6' long CD storage cabinets (I use Can-Am steel cabinets from Canada).  The LPs are stored in custom built wood/melamine in a music storage room (storage shed & garage for 5,000+ LPs).  The 78s are stored mostly in the music storage room by genre and size 10" and 12" on the bottom levels.  Also, unsorted in the storage shed and garages (I just haven't gotten to them and moved last year).  I don't have more than 100 CDs on a rear corner of my listening room-a major coup from my last home.  Just equipment and seating.