Unless you decided to take him on before Chuck or Jasmine, he shouldn't be overly
difficult. Obviously he may be a bit challenging if you started with Chikorita or are
using other sorts of Grass-, Ground-, or Flying-type Pokemon (or even a Dragon-type if you
have one), but hopefully you have some solid Pokemon to take him out. Fire-types aren't as
good as you'd think due to all of Pryce's Pokemon having attacks that are Super Effective
against them (same with Rock-types), so Fighting-types are the way to go.
After beating him, he'll give you the Glacier Badge, which lets you use Whirlpool outside
of battle, and he'll also give you TM07, which contains Hail. How exciting. Why not
Avalanche, you cheapo!
Anyway, leave the Gym and you'll get a call from Prof. Elm. He tells you to turn your
radio on on your Pokegear. Do so, and you'll find that all of the channels have been taken
over by Team Rocket! They've taken over the Radio Tower and are broadcasting their message
out to Giovanni, their missing leader.
Not good! Well, since the guy blocking your path east still won't move, you'd better take
care of Team Rocket once again! Fly on over to Goldenrod after healing your Pokemon,
pronto!