Since Dr Slump is an older show so the music releases seem limited.. You can still get some music if you look:

Dr. Slump Music Collection (Animex Series Limited Release) 2004

( Columbia Pictures)

This CD has a number of BGM tracks from the Dr Slump & Arale series plus a number of the opening/ending themes mixed together. The amount of dramatic music indicates this may be tied into a Slump movie but I’m not sure. The quality is superb far better than any of the anime I have which leads me to think that it was remastered for this release.
Song Title English Transation (Tentative run through altavista by Musashi)

Tracklist:
1) Opening
2) Ambition to travel to Outerspace
3) Peaceful Penguin Village
4) Goodbye Globeflower (Yamabuki?)-Sensei
5) Dr. Slump takeoff!
6) Planet Yukaina
7) Mashirito’s dream
8 ) King Mashirito of Outer space
9) Wierd Planet~Okakaume Planet
10) Ribgigo combat mission!
11) Concerto of Mishirito
12) Dr. Slump -Space Offense and defense
13) Arale vs Caramel Man ~Defeat of Mashirito~
14) Ending ~??? Super Disco~

Dr Slump Songs ( Columbia 2003)

Again this is from Dr Slump & Arale-chan rather than the new series. It contains mostly image songs ( 20 on 2 CDs). It comes with a booklet with song lyrics. I must say I love this CD, and have been listening to it often since I got it.

Front

Back

OtherCDs ( out of print?)

Dr Slump Orginal Soundtrack By Funta

Don’t own this so can’t give much more info then the official links:

Funta’s Site

Sony’s Listing