I've been trying to sort them out on Twisty's - this is what I've come up with: the Denisa that I think you're looking for is Denisa Hildebrantova (Czech), and while there are several model agencies with a few pics and some coverage of a beauty contest, not much real information. She has a small modeling website at www.denisah.com/ . I couldn't find anything on WhichPornstar or EBI or EGFD or IAFD. She did some stuff for Pure Beauty Magazine, but I don't have them (and there is another Denisa there to complicate things).
Denisa C (in the orange party frock) is confused with her on lots of sites - also Czech and goes by Deni on EBI. Denisa D (another Czech) is Gina on EBI, Gina A on WhichPornstar (Denisa B - Samueline de la Rosa - Elis - Julie - Danae - Gyna - Jasmin - Gina Lee - Denisa Brazdova). Veronica da Souza also ends up as Denisa, but that should be easy to figure out. I haven't a clue on Denisa S (claimed to be German).