I agree, Journeyman would be a good place for you. You have the experience of crafting costumes, but just not the experience with competing. A lot of cosplayers start competing really soon after they start making costumes - myself included - so it's a bit different for them.
2014 Conventions :
Katsucon (Washington, DC) - Megacon (FL) - Colossalcon (OH)
Upcoming costumes : NiGHTS from NiGHTS: Journey of Dreams, Princess Kraehe (anime) from Princess Tutu, and Zidane Tribal from FFIX!