I want Breloom to have Spore but I didn't know it could only learn it as a Shroomish :(
Are you asking if there is a Spore move tutor in B2/W2? because there isnt. the only way to get Spore on Breloom is to level up a Shroomish to level 45.
hide this if it didnt answer your question.
Source: http://www.serebii.net/black2white2/movetutor.shtml and http://pokemondb.net/pokedex/shroomish