I'm just wondering if anyone knows if 40mm film is available to buy to use for this camera, and if so, where could I get it. Can I use any other kind of film for this camera?
fhotoace is right about you not needing 40mm film (Not even sure such a thing exists/existed), but he's wrong about 35mm (135) film. Your camera actually uses 126 film. It's the same size as 35mm film, although it doesn't have sprocket holes and the images were square. Unfortunately 126 film is no longer available. No one makes it anymore and the last company that had any (a company called Solaris) has sold everything they had in stock. There might be a few people who still have some film in a fridge somewhere but it will probably be very expensive.
However if you're fortunate enough to have a 126 film cartridge in your camera, or if you can find one to buy (on ebay or wherever) it's possible to load the 126 film cartridges with 135 (i.e 35mm) film. Here are instructions on how to do that http://www.instructables.com/id/Instamatic-Retro/
And here's a video showing the process http://www.youtube.com/watch?v=vuhM7McQOpc
Remember you have to do it in a darkroom (or changing bag) with no light at all so it might be a good idea to practice a few times in normal light first.
Also if you want to do this you'll probably have to develop the film yourself. As far as I know, no one offers 126 film development anyore. Black and White film is easy to develop at home (plenty of tutorial online about how to do that). Colour can also be done at home, you can buy colour development kits that contain all the chemicals you need and you can a regular developing tank. I haven't developed any colour film (looking into it though. Might consider doing it a bit if it works out to be cheaper than sending film out, but I don't think it will). Anyway there seem to be 2 things that make colour development more complicated than black and white. The temperatures of chemicals necessary are much higher (black and white is generally done 20 degrees celcius, at most 24 which is about the temperature of tap water) and you have to be accurate with the temperatures for colour or you get extreme colour shifts. The second thing is colour development chemicals are more toxic than black and white development stuff so you have to be extra careful.
Anyway if after reading all this you're still interested in trying it then good luck.