I use the draw tool for rivets in PSP.
You can set up a line that is a row of dots. The drop down box in the "draw" tool window has a selection of different lines in it. You can create a new type of line by clicking on the "line style: custom" button. You can alter rivet size, spacing etc.
By creating two layers of rivet lines, one vertical, one horizontal you can edit them easier.
For raised rivets I first create all the rivets in black. Then I copy these, change the copied rivets to white and paste them offset diagonally one pixel back over the black. These are then merged with the black with the "effects/inner bevel" tool (thanks, whoever posted that tip). Then you just fade the rivet layers to taste.