Help with networking a PS3 and an ipod touch

It's no surprise that the  Apple support website would suggest their very own product, but you definitely don't NEED to go Apple for "compatibility."  In this case, it's not like software that has to run on  your Mac, it's just that your Mac has to have wireless capabilities.  Of course, if you have the router near where you have the iMac, you could always hard wire it anyway.  When I'm looking for stuff like this, I often start at Newegg to read user reviews of various popular routers.   
 
Now, I will tell you that the PS3's built-in wireless is Wireless G, so unless you want to buy an access point along with the router, you want to look at a Wireless G.  One of the most popular Wireless G routers is this: 
 
http://www.newegg.com/Product/Product.aspx?Item=N82E16833124190  
 
It should do you just fine, and it's pretty cheap. 

Wow sounds like you use a LOT of your neighbours data. I tend to play it safe with things like that and don't use too much but I guess your in the US so he probably doesn't have a data cap anyway. If that sort of thing happened to him where I'm from he'd be hit with some very serious overusage charges and would discover the scam very quickly.
 
On your router question just make sure you check up some user reviews on it to be sure it doesn't have issues with the PS3. Some modems give you grief trying to get Nat 2 on the PS3 even though they're new.

Yea, the PS3 is a wireless G, but your Macbook is wireless N.  I'd get a dual band N router so you can have the PS3 doing it's thing, and your macbook doing it's thing without much interference.  That being said, set up is usually pretty easy with most routers nowadays (browser based) so hopefully you won't have any problems when do get your router.

" @irishdoom: You forgot to expand upon the reason the WRT54GL is so popular: it has the ability to make use of free third-party firmware that vastly expands its abilities. It's basically a $300 router for $50. 
 
I have a WRT54GL and run Tomato, but there is also DD-WRT and some other less popular firmware options. 
 
As far as WiFi compatibility goes, it's an established cross-platform standard from the IEEE, 802.11. You really aren't missing out on much by not getting an Apple router. "

The only good thing about airport base stations is they act as a wireless usb print hub with minimal effort.