Ditto, well said Sam =D. I know this is an older post, but if my minimal experience can be helpful, I'd like to give it.
Take the advice of the others...make a couple knives from rail spikes first. See if you naturally have the skills and hammer control necessary. If you don't, practice...and don't get discouraged. A LOT of flubs in forging can be fixed in finishing, just be sure to forge with room for error at first.
I've made four blades I count as successful in my life, of five attempts, over the course of about six months or so. The last being a 25" nagasa (blade length) Japanese style katana. I had no previous bladesmithing experience, nor blacksmithing experience. All I had was the internet, a serious amount of determination...a willingness to learn, with an understanding that LEARNING meant BEING CORRECTED...sometimes very abruptly..and the advice of some VERY skilled craftsmen, including Sam from above, and many, many others.
Here is my entire body of work for you to browse through: My First Knife Knife #2 Osoraku Tanto (same tanto as below) Shobu Tanto First Full Length Katana First Japanese Sword (Cont. from above)
The common theme in all the above threads is that I made mistakes, kept on going...and took criticism with gratitude and respect. If you can do the same there's no reason you can't forge anything you like, given enough time and effort =D.
By the way, I'm just now getting back to the forge after a year or so break, so I get to start the learning process all over again lol!
Good luck to you!
Cris