Theres also a company out there that has larger flat plate deltas that they cover with target squibs. They fly by and folks with Shotguns shoot at them. When they hit they get a shower of wonderful flashes.
TopDawg or the Bulldawg or the CoroRu (spaduk has the plans for that) build fast, go fast but are not really maneuverable for Combat. Sickles and Flippers are ok for combat, though my Flipper I think is a bit heavy, Sickles were some folks favorites.
But Deltas suffer when you go and turn them. They bleed way too much speed off when you pull tight on them, then you're just sitting there while someone with a conventional setup comes by, snips you and flys away.
Chunky C has the SPAD plans on his site plus a ton of other plans at
http://spadfest.rcspads.com/index.php?cat=25
SPADuk site
http://www.spadcombat.co.uk/spad/
Chris's site with some of the plans
http://www.chrisspad.com/planes/main/mspp.html
I've got to sit down and do some work for the original plans, it's enough for now to know they are out there plust Draftman has them in DXF format.