Thanks PM...unfortunately the reason I bought seedlings was because NO one in my area sold Feijoa's at all...the only nursery that it and was told it was a NO name (seedling) variety...plus I totally suck at "grafting",lol...tried several times and NO luck! 
Oh, well some kinds of grafting work better than others, just make sure to get the cambium(green) layers to match up very well. If not matching then ehhh... dead graft. A good beginner graft is the cleft graft, I used this on apple trees and the grafted tree set flowers first, no leaves nothing but the branch and flowers. Most of them set fruit but I only left one which become a tasty Dorset apple. As for the lack of feijoa's in your area, try asking for nice scionwood of fruiting fejoa's once you get good at grafting.