Lowes was having a major clearance in their lawn and garden section and I picked up several: Russian Sage, ornamental grass and another outdoor plant that the name escapes me now. Does anyone know how I should go about putting these in the ground? I have leaf mulch and molasses, compost and Bio Form dry fertilizer readily available. Should I use anything else? Oh, and one more question how deep should I plant these? I'm confused about how deep to put them down cuz if I then add the mulch to the top I worry that the trunks will rot.

You can find bed preparation on this site in a number of places.
Check where you are going to plant them first to ensure the sun orientation is correct. Remove the plant from the container and brush off any loose dirt from the top of the root ball. This is how deep your hole needs to be. Don't leave loose dirt in the bottom of the hole, the plant will sink overtime. Return only the soil that came out of the hole, settle with water.
Mulch should be 3-6 inches deep but taper it down to 1 inch near the trunks to avoid problems.
Tony M