I do not. Recently, however, I searched the site for ways to use real hazelnuts, and seeing as you're having trouble finding an extract, I thought I'd throw this out there. The two methods that looked most promising were these, which are quoted from the original posts--the "I" is not me:
1. I roasted 3/4 lb hazelnuts in a pan until browned and then tried to remove skins as best I could before finely chopping them. I added these to a mason jar and poured Sobieski vodka over the top of them. You could definitely use a finer vodka and I have even heard of using brandy. I wanted a neutral medium. It's been a week and it spells amazing. The hazelnut taste and aroma are very present. I'm not sure what proportions I'll use it in, but I'll probably add some at transfer to secondary and then maybe more at bottling. Cheers!
2. Here is my experience making hazelnut extract. I decided not to use hazelnut extract bought from the store because I didn't want the beer to come out sweet. I bought some filberts, which I guess are hazelnuts. I bought two 2.5 ounce bags, I roasted them in the oven for a half hour or so. then the outside of the nuts peel off...so you can just rub them between your hands and the outside falls off. then I crushed them with a hammer and put them in a grain bag in a quart of water on the stove. I kept the temp at around 150 to 160 because I worried about tannin getting extracted. I check it after a half hour, then at an hour I noticed a big change...at an hour and a half I noticed even more change so I let it sit in there for over three hours. It was really roasty and hazel nutty. next time I might boil it down with the nuts not in it to see how concentrated I can get it. I think I'm going to add more hazelnut extract when I bottle it.
I've got some hazelnuts, already blanched, and some cheap vodka, so I'm probably going to give the first method a try. Good luck however you go.