Here's a few links, some of which you may find helpful on your quest for knowledge:
Practicing
Practice Practice Practice How to practice bass
Pacman's sure-fire scale practice method How to practice bass
Online lessons
A LOT of Free Lessons, how to's and other stuff from me! TB member Dmanlamius has free video lessons
Who do you think has the best lessons on youtube? Who's the best youtube bass teacher?
http://www.studybass.com/ Bass studies,online metronome, fretboard printer, bass clef tutor,more.
http://www.activebass.com/ Tab based lessons by members for members covering all types of bass instruction.
http://www.playbassnow.com with MarlowDK including videos.
http://www.thelibster.com/bass/ beginners' guide/lessons, tech advice,drills, bass sound files,tips,Q&A, links/more .
http://www.cyberfretbass.com/index.php For all bassists
http://www.musicdojo.com/index.asp Online bass course (5 day free trial)
http://www.cliffengel.com/ Free and paid lessons from Cliff Engel
http://www.talkbass.com/forum/showth...92#post6857992 Cliff Engel customer reviews
Books and instructional materials
http://www.bassbooks.com/shopping/default.asp Books, DVDs, all styles and methods
looking for "the bass guitar bible!" Looking for the Bass "Bible"
http://playbassnow.com/recommended-learning-materials/ MarlowDK's recommended books
Best Theroy book "Best" theory/harmony book
Book list for GI Theory Links TB Book Links - all styles,levels and techniques
Theory
Need help reading bass clef Read bass clef
I need to learn how to read music for bass, how do i do it? Learn to read music
Reading Music Learn to read music
http://www.talkbass.com/forum/f22/sight-reading-486398-post6521582/ Improve site reading
Introduction to Scale and Chord Theory Intro to scale and chord theory
I need basic music theory help... Learning Theory
Circle of Fifths Question Key signatures/Circle of 5ths/Cycle of 4ths
Circle of Fifths Question Circle of 5ths (spreadsheet format)
The reason for Modes Reason for modes
Modes...How to use them practically in music. Using modes
Music Theory/General Instruction Links TB Gen.Instruction Theory links list
Theory Forum FAQ and Links Theory (from the DB side of TB)
http://www.teoria.com/ Online study of music theory. Check out the tutorials, exercises and reference dictionary
Getting creative
Where does creativity come from? Where does creativity come from?
http://www.talkbass.com/forum/f30/creating-bass-lines-8154/#post80043 Creating bass lines
Bass Line Construction: Target Approach Creating bass lines - Target Approach
Scales and improvisation Playing scales
http://www.talkbass.com/forum/f22/what-good-ways-approach-playing-over-chords-503344/#post6770334 Creating bass lines for a jam
what is in front of/behind the beat? Playing behind/ahead of the beat
The 'feel' "Feel"