Bad advice: the 22-gauge connectors will NOT work properly with 18-gauge wire. The wrong gauge wire will not seat properly in the slot and either cause strands to break off when punching down the wire (gauge too large) or will not achieve a solid connection (gauge too small).

www.onlinecomponents.com seems to stock a pretty good selection of Pancon IDCs, but they do have a $50 minimum order. For 18-gauge wire applications search for CE{p}F18-{n} for "end" connectors (wire ends at the connector), or CT{p}F18-{n} for "through" connectors (wire continues through the slot in the connector); {p} is the pitch (100 for 0.100", 156 for 0.156"), and {n} is the number of positions. e.g., CE156F18-7 for a 0.156" pitch end connector that accepts 18-gauge wire and has 7 positions.

You should also get one of the Pancon manual insertion tools; Terry sells the MMIT-100F and MMIT-156F for about $10 cheaper than www.onlinecomponents.com.