I use the commonly available ground almonds (next to the slivered, blanched and whole dried almonds in the bulk bins) where almond flour is called for. If it needs to be more finely ground, more "floury", I'll whizz it in the F.P. for a while, carefully (don't want almond butter).

Some Health Food Stores *might* carry actually Almond Flour but I've never seen it in my travels in Canada.

There are online sites that claim to have nut flours but I haven't actually tried them to find out if they are any different than just plain ground nuts.

Hope this helps.