If you're interested in messing around with NPCs in console, I recommend looking into UGM. UGM was a project that I was working on pre-gmod 9. UGM 1.5 would probably be best for you, but I don't seem to have that anymore, so check out UGM 1.3, attached. This was released over six years ago, but since it's not relying on gmod in any way (only the source engine), it still works fine.
Otherwise, if you're set on using ulx ent, it's possible to spawn npcs with this command, but you'd need to check the valve developer wiki on the exact details.