Fireplug, you can upload the raw .AHF file onto the forums via a link. But, to get that link, you have to upload the film to a web server of your choice. There are plenty out there for free, or you can ask someone on these forums to host the .ahf footage for you.
Just so you know, most people on these forums post .WMV videos. To make these you either have to re-record your footage from the AH FV using Fraps or a similar program, or you can try to export the .AHF footage from the AH FV, which is quite difficult from what I hear.