Problems finding firmware version on a locked iPhone 4

I bought an iPhone thinking that I could unlock it for cheap but apparently the server of the network that it’s locked to is offline for another week and it’s going to cost £40 ($60) just to obtain a code from them.
So the problem is that I’ve tried to use F0recast and Tiny Umbrella to retrieve my firmware model and have so far failed. I’m using windows 7 and I’ve tried 3 different versions of F0recast and I’m getting the error ‘unable to load DLL iTunesMobileDevice.dll’, I’ve tried downloading the .dll in question and inserting it into C:\Program Files\Common Files\Apple\Mobile Device Support but nothing happens. I’ve tried an older version of iTunes, even a different computer but with that I get a different error message ‘The type intializer for ‘Mobile.Device.Mobile device threw an exception.’ When also trying to open f0recast.
I’ve also tried Tiny Umbrella but that insists that I run the program as an administrator every time, although I already am and it can therefore not start the ‘TSS Service’.
I know what you’re thinking, buy a macbook but on a serious note can anybody help me here? After I know the firmware I can crack on with a redsn0w install or something similar.
Unless anybody knows something I can install where it wouldn’t matter what firmware I was using? I’m tempted to buy one of those sim cards for a hardware crack but I really need to get it done quickly as possible or I have to go back to the shop tomorrow, cancel this sim and activate another large one to put in my old ancient phone.

Argh the headache!
Thanks for reading, any advice is fully appreciated!

 

I can't get into the phone to check the settings, so it looks like DFU mode and redsn0w could be a viable option.....

 

I'm in DFU at the moment with the redsn0w menu up on the screen, so far I can't see any firmware information

 

Wicked, thanks.... I got paranoid and tired to download a blob first.. it came up with an error but it's back to normal now. I'll give a straight jailbreak a go. Will this unlock it too? That would amazing if so.

 

what's the best way to unlock it without waiting a week for a large corporation to charge me lots of money to press a button

 

it hangs up on 'please wait while your build is being identified'

Exploiting with limera1n.

The phone is back to the welcome screen now, could this be because it's not unlocked yet?

 

Ok last update... I've tried restarting and using TinyUmbrella as admin, nothing.

10/04/2012 00:39:13.168 Cannot Start TSS Service DO NOT TRY RESTORING YOUR DEVICE!!! TinyUmbrella MUST be run as an Administrator or root!