I use Pres-On acid free z-core boards. Their web site is http://www.pres-on.com/products.cgi?pclass=z10
I always order by phone, their web site is not friendly but otherwise they ship reliably in virtually armored containers that insure the boards arrive intact. I use the hi-tack boards. I do this for prints from 8x10 to 24x30. Since I crop depending on the image, this saves cutiing odd shaped mats - I print leaving a white border appropriate to the image. I dislike mats anyway.
I don't need a press, but do the following: Use a mat knife to begin the separation of the slick cover that protects the tacky service (this is the most difficult step - find where the line is under a bright light), align the print with the edges of the mounting board maintain the position with a few (4-6, depending on the size of the print) Oxo kitchen clamps, roll back the end of your print a bit at the end where you started the separation, roll back the protective tack cover about three inches and fold a crease in it so lies back flat, fasten that end of the print to the exposed tack by pressing from the middle of the fold out to the edges. The print will not move now, so remove the clamps and gradually pull the remaining protective cover three or so inches at a time, smoothing your print as you go - voila! you are done.
To prevent the print from touching the glass in a frame I use Frame-Tek spacers http://www.frametek.com/
When I submit prints framed this way to exhibitions hardly anyone notices that they aren't matted. It is a very clean look.