NeeD Help with Team

Ok, so im done with Silph Co., and ive beaten koga.
my pokemon:

Blastoise
lvl 38
water pulse, surf, bite, protect

Arcanine
lvl 32
ember, hyper beam, bite, growl

Fearow
lvl 34
peck, aerial ace, mirror move, leer.

Jolteon
lvl 33
shock wave, double kick, quick attack, hyper beam.

Marowak
lvl 32
bonemerang,bone club, rock tomb, brick break

Haunter
lvl 32
dream eater, giga drain, toxic, curse.

i already know that their moves arent the best.

im going to teach blastoise hydro pump and cannon,

ill teach arcanine fire blast and hopefully it will learn flamethrower or some other good fire move.

im going to likely teach it drill peck and fly.

jolteon i dont really know what im going to teach

i know that im going to teack marowak earthquake, and maybe even a fire type.

im going to make haunter re-learn hypnosis, and shadow punch,
and hopefully it will learn other ghost moves.

the big problem im having right now, is that, my pokemon are way to underleveled.

i remember, in my last profile, i beat rockets so easily it was boring.
but now, its a struggle.

I dont really know how i beat Koga.

I have the right pokemon, haunter to do it, but i need to level him up alot, since sabrina's psychic moves will defeat my poison/ghost haunter.

i cant evolve haunter, since i dont know anyone who has FRLG near me.

Now Sabrina and Giovanni will be a big struggle if i dont level them up enoguh. (blaine will be easy, since i have blastoise and marowak on my side)

please tell me- where is a great place to train before fighting sabrina?
and btw i already know about the exp share. i know where to ge that but i dont have fly yet.

train your haunter the best you can. and if arcanine still has bite, then train him too. tahts who i used and i beat every pokemon with it.