no, there are more than 30 ways to cast on!
some are very similar.
norwegian (or twisted, or german) long tail
Knit and purl long tail
2 color long tail (simple 2 color)
2 color long tail, braided (and 3 color braided, and 4, and 5 (are each of these a different cast on?
Knit cast on
Cable cast on
Knit cast on in knit and purl
knit cast on in purl
cable cast on in knit and purl
cable cast on in purl
eyelet cast on simple
emily ockers eyelet cast on
tubular cast on (i know 3 ways to do this, all very different)
latvian twist cast on (actually a cast on with several rows of knitting, then twisted)
channel island cast on
crochet cast on
Picot cast on. (again, several varitions)
simple cast on (even this cast on has some variations!)
lace cast on (a sort of knit hair pin lace, then you then pick up stitches from the lace)
Turkish (really these are variation of each other)
and others …
there are lots and lots of ways to cast on! i don’t know them all yet (but i know all the ones i listed, and some more (i always forget some when i make a list)
now, mind you, i use long tail (simple or some variation) about 50% of the time, (if you don’t know this cast on, learn it!)
about 30% of the time, i use a tubular cast on… (the kitchener/or italian method, (see Big Book of Knitting)
the other methods are “3 needle tubular” and “waste yarn tubular”.
10% of the time, emily ocker cast on.
the rest of the time, i use an other cast ons…
(go to my blog, (link below) and find a link to photogallery. my socks have lots of different cast ons.)
i don’t have a tutorial for cast ons, but i do teach a class about them (none currently scheduled)
The fun part of knittign is you can do it for 45+years, and still have things to learn!
there are several ways to do decreases too… and increases. there is always more to learn!