This very weird Mexican horror-spoof film features a foot tickling scene. Not a great one; the woman isn't all that attractive. But it's still a mainstream scene. The movie is available from Sinister Cinema; there's also a copy on eBay right now.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=41617&item=3338374168
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=41617&item=3338374168