Hi total waz,
Good news total waz, it most certainly is possible!

First you just need to find a good fast free file sharing site - this one is very good, yet, if you desire to choose a different one then there is a useful list if you google the words "free file hosting". On the hosting service I have linked to, all you have to do is click the browse button and find the folder marked "saves" in your R:TW directory. This directory could be in either "C:\Program Files\The Creative Assembly\Rome - Total War" if you have the Gold Edition or "C:\Program Files\Activision\Rome - Total War" if you have standard Rome: Total War. After you have found the saves folder you need to find your great save, it, hopefully, should be named as what you named it as when you originally saved it. Double click on it in the browse window, click the "upload" button and let the uploader do it's magic! The almighty uploader will notify you when it has completed it's work! After that just copy and paste the link into your post, hit sumbit, and your done! Good luck, cheers!