The most popular Creed scents for men usually are Green Irish Tweed, Millesime Imperial, Silver Mountain Water and Himalaya. Many also like Bois du Portugal and Original Vetiver.
I'd start with the first four and give them all at least two-three full wearings (one sample vial should be enough for that). Or wear whichever ones appeal to you out of the vial. Read the reviews
here, they are very helpful to a newbie and will help you better understand the fragrances you are trying.
Once you know for sure if you like any of them enough to buy a bottle, you may wanna consider buying it from the Basenotes Classifieds as you usually will save a lot of money that way. The other way to get Creed and not pay an arm and a leg is to buy a 2.5 oz tester bottle on eBay or an online retailer. This would be a lot cheaper than getting them from Nieman but you have to make darn sure you are buying from somebody who has a proven track record of not selling counterfit Creeds (many full 4 oz Creed bottles on eBay are likely to be fakes).
There are dozens of
Creed-related topics in the Male Fragrance Discussion section, prepare to do a lot of reading and if you're interested enough you will get a lot of information from them, as most nuances of the fragrances themselves as well as validity of Creed's marketing hype and tips on how to avoid fake Creed had been discussed ad nauseum over the years. Don't feel discouraged by many who dislike or ridicule Creed fragrances, they were a great transition point for many of Basenoters from mainstream department store stuff into niche perfumes and are enjoyed by many here.
Good luck!