I have just reached level 30 and was wandering how I can continue to level up my skills? (apart from the use of skill books).
Wanted to know if you still get the opportunity to get more skill points or whether that's it now I'm level 30.

get the dlcs. then you can level up to 50

If you don't have the DLCs, the only way to get your skills up after 30 is with Skill books, though, after Lonesome Road and Old World Blues release, you will be able to level up to 50.