which form do i use and where can i find it for:
applying for 50% of my wife SS income
I suspended my SS till age 70 (i'm now 67) . my wife is at full retirement age and starts receiving her SS in early may.
Technically, the application form for Social Security spousal benefits is an SSA-2, but Social Security no longer uses paper application forms. You can file by phone or in-person by contacting your nearest Social Security office, or by calling 1-800-772-1213. You may also be able to file online if you haven't previously filed for benefits (https://www.ssa.gov/retire/).
It worries me that you say you've suspended your SS benefits. If you actually did file for and suspend your own retirement benefits, you likely won't be able to draw spousal benefits. It sounds like what you actually wanted to do is file just for spousal benefits only, and defer filing on your own record until age 70. If that's the case, and if you did actually file for and suspend your own benefits, it may not be possible to do now unless you are still able to withdraw the application that you previously filed on your own record (https://www.ssa.gov/planners/retire/withdrawal.html). There isn't enough information in your question for me to be able to advise you, but you may want to contact Social Security ASAP to discuss your options.