Ive been playing guitar for four years now and want do something of my own. The problem is I don't have the time or money to learn computer software. (Also my computer is pathetic and would not work with recording software). I was just thinking of writing songs on guitar and just recording the song on guitar. Is this a common way recording music projects or is it odd?
Everyone has their own way of recording and there isn't really any "Odd" way per se and as long as it sounds how you want it to sound than it is good. If you mean recording songs with no other instruments you may need a lot of layers (unless you're Steve Vai) depending on if you want it to be more of a solo that goes on for a full song, or just strumming, and picking, or an instrumental without words, etc.
If you don't have the desire to learn software, you can still create an extremely good sounding product using a multitracker. They can do pretty much everything that software can, but are usually easier to learn and don't need you to have a good computer. If money is tight they can be bought used.

There's a section about them including a load of recommendations in the interfaces sticky.
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