If the computer I used to file my taxes last year died, and I cannot find my AGI from 2017 to efile. Is there any way to find that info so I do not have to mail forms?

You 2017 AGI is very very likely NOT the sum of the wages from your W2s.  If you don't have a copy of your return from last year you can request one from the IRS (but that takes time). Probably best to file by snail mail this year. Sorry.