For tokens I use two common methods:
Buy chipboard off of amazon of the desired thickness, whole sheet white mailing labels, and a can of spray clear coat. I design the sheets using FOSS (free open source software: in particular GIMP for raster graphics, Inkskcape for vector graphics, and Scribus for desktop publishing layout of the page), print it to the label and adhere it to the chipboard, and typically use a circular blade cutter rather than something like an Exacto knife with a good non-slip straight edge.
Purchase bingo winks and a circular paper cutter (I believe 3/4" is what works with them, but it might be 5/8"). Again, use FOSS to design the sheet to punch, punch out with paper punch, peel and adhere to the winks. A quick, dirty, and cheap way to make circular tokens and it worked better than an arch punch for me.
If you want no-cut tokens, whole sheet mailing labels and wooden craft squares (circles, ovals, and other shapes available) are another quick way to go. You might need wood glue with these also, and coat them again after applying the labels to help keep them adhered.
For cards, I go cheap. Old CCG common cards for cheap or free (I have a ton of Babylon 5 CCG cards) or thrift store copies of *Apples to Apples for bridge sized cards plus penny sleeves is how I do it. Print on plain paper, cut with a good guillotine or photo cutter, and then sleeve them with a real card backing. I find it works quite well.
If you are going to buy an existing game and apply paper to it, I suspect you will have to rough up the surface to remove the coating on it (sandpaper most likely or actually peeling it off) then print to cardstock, cut, and glue it on (no wrinkle glue). Then seal it.
If you want to know how other people do a lot of things, then the complete resource is found here on BGG for <em>All the DIY Links You Never Knew You Needed</em>.