Depends on what your looking for Irish? Do you want a badass American Muscle car that you can drive around and show off, or do you want a cool car that is economical?
Here in the good old U.S of A it really is between the people who can afford "Gas Guzzler's" and Economically sound vehicles. Most good/fancy American cars will suck your wallet dry so make sure your not making insane drives around everywhere or wiping it up and down the road too often. Otherwise you'll find yourself broke. On the flip side theire are some really nice Economically sound cars that can save your wallet and still look good. Additionally it really comes down to what car dealership you trust. Me being a Chevrolet/Ford guy here are a few I recommend.
Now this bad boy is Chevrolet's latest and greatest Muscle Car creation with all the gismos and gadgets you could think of. 17 City and 28 Highway it's heavy on gas but makes up for it inpower with the VVT V6 engine(323 horsepwoer baby), Speed Control, and Telescope Steering. Plus it has a built in phone system, Wireless router for Bluetooth, MP3/iPod hook up, and serious speaker systems. Manual or Auto Tranny this car has good reviews for handling, but you'd have to see bout parts as your in Ireland and I'm unsure the shipping costs for replacements parts. Overall good car, drove my buddies last year and so badly want one.
Plus it's famous cousin, the 2010 Camareo, was featured in Transformers if you want something notable for your Nerd freinds. ;)
The Ford Mustang GT series, a truely American car for a truely American experience
This beasty runs on an OP 5.0 V8 engine that torgues it right off the road(and burns series rubber real fast according to my freind). Definitly high price, but if you can afford it this car will make all your buddies at the local Pub start goi9ng teary eye'd and fully jelous. This car is more about performance than luxury, but still has your standard Stero's, iPod/MP3 ports, all the comforts of a car, and a customizable sun room if you pay for it. Only a 2DS so not alot of packing/passanger room but still worth looking into.
It's younger brother the Shelby GT500 is famous for being one of the fastest Muscle cars out there, and if power and speed is what you need I'd start there.
Another pick from the modern Muscle Cars of the day this car emphasizes luxury and speed over performance. Shitty gas milage and not nearly as much torgue as the previous mentioed cars, but it still can meet the Need for Speed. Plus this thing is quiet when you want it to be, and my freind the mechanic says it's easier to replace on parts than the Camareo's and other Muscle cars. Good Interior with basic designs, and a customizable Roof and Stero system.
These are my Top picks based on my driving experience and chatting last night with freind's who deal with these cars on a daily issue. TBH Irish you need to ask yourself how much your willing to spend, and if you want a Modern Muscle vs Classic Muscle Car. Both are relatively expensive either way, but Classic's tend to be cheaper and you can often find independant buyers looking to off their cars for a bit of cash. If you have the expertise, or a freind with the same, you could buy a used model and fix her up as a side project. Best of luck though mate, hope you find something to your liking.