There are several videos on wire inlay, and the ABS school teaches a class on it. Joe Keeslar is good at it, and as said above, has a kit with instructions.
Bill Moran taught me how to do it.
The wood needs to be fine grain, not too hard, and not brittle. Curly maple is a good starter wood. The wire is called jewelers wire, and is a flat strip about 24 gage and 2mm wide (get half-hard temper).You make a tool (or a set of them) from old hack saw blades. They look like small engraving tools. The blade is ground to the thickness of the wire, and about 3mm long ( to make a cut 3mm deep). Harden and temper the blade, and mount it in a wooden handle, and sharpen the edge. Make them in 2,4,and 6mm blade widths. 6mm is about as wide as works well. Sketch the design on paper, then re-draw it on the wood in pencil. Start making the cuts by pushing the tool into the wood, rocking it out, re-inserting it just down the line....and so forth until you have cut all that line. To insert the wire, draw it through a piece of folded 120 grit sandpaper to stiffen it and put a slight roughness to the sides. Using a very small mallet, tap the end into the cut and tap your way GENTLY along as it goes in. There is a lot more to it than this, but this should give you the idea. Bill Moran has a video on handles and wire inlay that shows the whole process well.