#1
I can play a couple of Specials tunes, but I want to get into playing stuff like Streetlight Manifesto and that kind of thing, any tracks to ease me in gently?

Ibanez SR506BM
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#2
listen to the songs, and pick one you like that sounds good and simple. google the tabs
#3
I guess Less Than Jake and Reel Big Fish have some songs that are more on the simple side you could use to break in.

She Has a Girlfriend Now and Beer by RBF
All my Best Friends are Metalheads by LTJ.

Oh, and Estampida by Ska-P.

Good streetlight to start with would probably be A Moment of Silence, then maybe say, Dear Sergio.
If music was the food of love I'd be a fat romantic slob.
#4
Try piecing together some No Doubt songs. Most of them are fundamentally punk rock oriented on a base level. But, Tony is a very Ska-influenced bassist. It's a good starting point to use as a foundation for more busy Streetlight-esque stuff. I play some ska these days, and it all started when my punk band in the later 90's covered 'Oi To the World'. We origonally wanted to do the Vandals' version... but our singer wanted his girlfriend to sing, so we went with the No Doubt version... it was one of those benchmark moments for me that expanded my horizons as a bass player.

http://www.youtube.com/watch?v=ZXTHBVS7Sjw

http://www.youtube.com/watch?v=hoL1Uxwk6vc

one of my favorite No Doubt basslines:

http://www.youtube.com/watch?v=JIm_6JsIQ3Q
"Punk Rock should mean freedom, liking and accepting anything that you like, as sloppy as you want, as long as it's good and has passion."