Heading to Las Vegas... any suggestions?

Neil, i can't be much help on the tobbaconist part of your question, but my mom has lived there since '96 and i have been there too many times to even count. You will have a blast and there is so much to do it is insane. Make sure you try and see at least one show while your there, La Rev (Cirque du Soleil) is a great one. Also, bring some dark dark shades so your girl doesn't catch you looking at the PLETHORA of beautiful birdies strutting around everywhere, lol. I know there are multiple tobacco shops out there, but like with most other places, the cigars sort of block the sun out for the pipes/pipe tobacco from the ones i have been to. I can't remember the names to any of them in particular, but a quick google search should get you some results. Hope you have a blast and let us know how it goes!

Be sure to go to Hoover Dam - not sure if they do the damn dam tour anymore, but if they do, it's worth every penny.

How about the duty free shops?
A friend of mine is going to Vegas next week also and I've asked her to pick me up some tins of Dunhill.
I've done a web search but it looks like there's nothing on the strip.
Please, someone help us out!

Been to Vegas for the pipe show a while ago. I think there is a B&M called "Tobacco Leaf" and they had 2 locations in Vegas as I recall. I did not attend either place, but I had planned to when I got to Vegas. IMHO, your best bet is to order some and have it delivered and held for when you visit. Don't forget the 200g virtual limit for duty purposes. And yes, bring some dark shades with you when you are there, lol.

Can't help you on the tobacco related stuff.
Everybody always raves about the casinos and the strip. Not my thing at all I like the outdoors. Red Rock Canyon National Conservation area is only just outside the city limits. The place is amazingly beautiful. Lake Mead and the Valley of Fire State Park are also fantastic places to visit. In the Valley of Fire you can view some ancient petroglyphs just a stones throw from the parking area.
Just amazes me that people spend big bucks to hang out in Vegas gorging on buffets and blowing dinero in the casinos and never leave the town. The natural beauty in that area is stunning. I'm not sure when the cacti bloom exactly but in any event it has got to be pretty this time of year and not brutally hot.

The best selection of tinned tobbacos in Las Vegas is at Tobacco Town. The one I stop by occasionally is off of 95 & Lake Meade, roughly a 15-20 minute drive from The Strip depending on the time of day and where on The Strip you are. They typically have the entire Peterson line, Dunhill's Nightcap EMP & 965, a number of McClellands offerings, and good amount of Mac Baren blends as well. They also have some bulk blends. Can't recall off the top of my head who they get them from. Tobacco Town also has the biggest selection of pipes too in case you're in the market. They carry Peterson, Savinelli, Castello, and Dunhill. Overall good people working with a nice selection and a nice lounge to enjoy a bowl or two in.
Tobacco Town off of Rainbow & 215, between a 10-20 minute ride once again depending on time of day and where on The Strip you are, has a ton of bulk blends. Mostly Sutliff bulks, but it's by far the most bulk blends offered by any shop in the valley. Not much in the way of pipes and they've scaled down their tin selection to mostly a few Sutliff blends. Like Tobacco Town it's overall good people working there and a great place to stop off and have a bowl.
There's nothing really any closer to The Strip. If you're into cigars there's the Davidoff store which I believe is in the Palazzo and Casa Fuente in the Forums at Caesars. Nothing pipe related on The Strip though.
Vegas is a pretty smoker friendly city. For the most part the only places you can't smoke are the stores or restaurants. I will say The Strip is a great place to find a bench and puff on a pipe while people watching. I always forget how much eye candy there is down there until I have to take a friend/relative down for a show when they're in town lol.
As a local I feel obligated to mention Neiman Marcus Cafe in Fashion Show Mall. It's a wonderful cafe attached to the store that you can get a lunch for around $15 a person and they have a patio area outside to eat at. This time of year it's perfect for lunch. Good food and interesting people watching.
There's tons of wonderful eateries, tons of amazing shows, tons of great places to smoke a pipe, and tons of fun to be had in Las Vegas. Enjoy it!

I can't help you on where to go. But I can help you on where not to go: The Davidoff shops in any of the casinos... unless you like paying a big premium.

I just got back from Vegas last week. I decided it was easier to order what I wanted and have it shipped to the hotel. In my case the hotel had a UPS store and required I ship it to the store. It cost me $8 for them to hold the package. It still worked out to be cheaper than shipping to Vancouver.

I thought I goofed lol. That first location is actually Tobacco Leaf. Didn't goof about the location though, the one I stop by is at Lake Meade and the 95.