My iPhone 3G's (not 3Gs) wifi has been really sketchy lately (won't see/connect to any networks), so after a network reset didn't work, I decided to try a restore. I restored to 3.1.2, and then jailbroke with blackra1n.
WiFi still doesn't work, so now I'm stuck with an activated iPhone that I can't get internet on since it's not unlocked (I'm on T-Mobile).

Is there a way to install blacksn0w without wifi? (I have internet on the computer, obviously, so I can download whatever I need, but not on the iPhone)

I've read and tired this http://www.hackint0sh.org/f230/95865-2.htm, but I can't connect with iFunBox/DiskAid, since the afc2add isn't on there.

Are there any other options available besides a warranty replacement? (to fix the wifi)

Well, since I don't have access to a Mac, I just downloaded some already activated IPSW files and restored using them. Then I used the previously mentioned (in the other thread) manual blacksn0w process to unlock.

Now my only problem is how to install RockApp (since the only way to install it on 3.1.2 is through BlackRa1n, which I couldn't use). Any ideas?

Why the hell do you want to use Rock app? Is Cydia not good enough?

I know Rock allows trial versions of paid apps.. However I am very skeptical of the product aside from that arguably good feature.

Agreed with Olethros. Just stick to Cydia. I had major issues after I installed Rock. And why didnt you install the Push and Wifi fix within Cydia to fix your Wifi issues?

Wifi and Push Fix can be implemented within Cydia. Push, YouTube, & WiFi issues are caused by hacktivation. To fix this issue, add http://cydia.iphoneil.net/ as a source, return to Section and look for "iPhoneil Utilities", install "Push Fix & Youtube".

Originally Posted by bmw

Agreed with Olethros. Just stick to Cydia. I had major issues after I installed Rock. And why didnt you install the Push and Wifi fix within Cydia to fix your Wifi issues?

Wifi and Push Fix can be implemented within Cydia. Push, YouTube, & WiFi issues are caused by hacktivation. To fix this issue, add http://cydia.iphoneil.net/ as a source, return to Section and look for "iPhoneil Utilities", install "Push Fix & Youtube".

Pushfix from http://cydia.iphoneil.net/ does NOT fix push notifications. It does fix youtube issues. This utility is generally not recommended. The original pushfix from the devteam is recommended in conjunction with the guide in this thread http://www.hackint0sh.org/f137/96714-post474376.htm

The devteam have hinted they are working on a better pushfix, no idea when or if that will be released.

I have never heard of the wifi issues being associated with hacktivation.

Using pwnagetool or redsn0w to hacktivate results in everything working aside from push notifications. This is one of the reasons I recommend pwnagetool over blackra1n.