Actualy the book needed is in booty bay, so it sould be eazy enuff for you. fishing just gets harder and harder, IMHO it is the roughest of the secondary skills. Cooking is eazy to level, ya just need meat and fire sometimes spice(insert favorite DUNE quote). first aid, that bugger is eazy. i have both cooking and first aid up to 300 but fishing... ya i am stuck at 175, it just gets harder and harder to level it for me, i still get adds at Booty Bay just verry slow, i guess if i put a lure on and moved to a harder spot i would get adds faster.
Just keep fishing once you unlock the 150 cap(if you havent already) you will level up. A Guldie was able to get to 225 only in darkshore...but has been doing it non stop for far too long(alchemest and need the Oily Blackmouth)