HI Ray
Welcome to the CashFlowDepot family!
Absentee owners are not a good list to mail to. Unless their house is vacant or they have a tenant who is not paying, they have no reason to sell.
You will do much better if you focus on VACANT houses. If they are in fairly good condition, they will be ideal candidates to buy with seller financing, lease option, master lease, or to get an option then do a highest bidder sale.
You can also get a list of evictions and mail to them. Some of these will be long distance landlords who will be motivated.
For wholesale flips, market to code violations and dead meters.
Best of Success!
Jackie