I see some photos of very very big whitetail and muleys and asked myself if there are specific areas that are known to produce such trophies and if there are the huge cost differences on the trophy quality like in Europe.
Can anyone enlighten me?
thanks..

For whitetails, look to Kansas, Illinois, Missouri, and that region in the US. And don't forget about western Canada for some more true bruisers.

Express.
Hunting whitetails is real cheap here in Sask. when compared to other places. Non residents must hunt in the northern 2/3 of the province and non Canadians need a guide. The outfitter I worked for used a combination of tree stands and stalking with good success. He has since moved to a new area further N/W and I haven't seen much of him since. You pay for licence and guide, no other fees. Getting your gun into Can. is a hassle but I think worth the trouble. The last I helped Gary my 4 guys from Mass. U.S. took home 3 5x5 bucks and passed a lot of smaller ones. If you are interested the outfitters here have an ass'n but not sure how to contact them. This could be today's project.
Mule deer are a residents only deal at present. CWD has been found in another mule deer west of my farm so the locals there can shoot as many as they want for testing.Mark

The beauty of deer hunting in the states is, you can hunt quite cheaply and still have a shot at taking a good buck. Residents obviously have the edge here, but with a little planning and research it is feasible for a non-resident to do unguided hunts on public land with reasonable chance of success. I hunt western states each fall over 1,000 miles from home and have had great hunts for minimal cost.

Since you live out of the country, you would likely be on a tight schedule and due to the logistics, cost of travel, etc., may only want to do this one or two times.

I your case I'd recommend hooking up with a good outfitter. For muleys I'd consider Montana, Wyoming or Idaho. For whitetails I'd look at Kansas, eastern Montana, South Dakota or maybe Iowa. About $2500/each will get you very high odds of coming home with an above average trophy.

If you're after only the real high caliber animals, (assumming fair chase hunting, no fenced enclosures) plan on several hunts and the possibility of eating tags and going home skunked.

If money and time are no object, and I was after a very top end muley, I'd look into Old Mexico. For a very top end whitetail Alberta or Sasketchewan.