Bass Guitar for Dummies is a great get started book. Your public libary may have a copy. www.studybass.com
is a free site. One of the better free how to play bass sites on the Internet.
Fake chord sheet music. Why fake chord? The bands that play your music will be using fake chord and will expect you to play from fake chord. Google the following:
guitar chords, "name of the song" the comma and quote marks help in the search.
The major scale pattern.
Major Scale Box.
G|---2---|-------|---3---|---4---| 1st string
Want to play over a C chord? Place the box's R over the
C note on your 3rd string 3rd fret and the box will
automatically place the correct notes for the C chord
under your fingers.
Using your fake chord sheet music; see the Cmaj7 chord and know that R-3-5-7 will make a good bass line for that chord. Then when the G7 chord comes up you fingers just know that R-3-5-b7 is what you will need for that bass line. Listed below are the chord tones (notes) you will need to get into muscle memory.
• Major Triad = R-3-5
• Minor Triad = R-b3-5
• Diminished Chord = R-b3-b5
• Maj7 = R-3-5-7
• Minor 7 = R-b3-5-b7
• Dominant 7 = R-3-5-b7
• ½ diminished = R-b3-b5-b7
• Full diminished = R-b3-b5-bb7
See a chord and play it's chord tones. As every key will have three major, three minor and one diminished chord it's a good idea to get your major, minor and diminished bass line chord tones into muscle memory so when you see a chord your fingers just know what will work. Now the song may only give you enough room for the root, or root five - adapt and get as many chord tones into your bass line as needed. Root on 1 and a steady groove from the other chord tones plus something to call attention to the chord change is what we do.
First things first -- Root on the 1st beat and then the 5 on the 3rd beat for R-5 when that gets easy and you can keep up with the music throw in an 8. R-5-8-5. That is about all you will need for Rock-a-Billy for quite some time.
Bass Guitar for Dummies will have how to hold your new bass, how to tune it, how to get sound from it and how to mute some of that sound - all the gotta know stuff.
Good luck and welcome to the bottom end.