Sounds about right to me. 'course it all depends on how many lines, etc.
Way back when I used to advertise in the service guide (btw, not the best method of advertising, and also attracts the low-end customers more), I used to pay about those rates for an ad like this;
BEAVERTON / TIGARD AREA
Professional Weekly Lawn Care
Pruning, Clean-ups, Mulching, etc.
Being as I don't service all of the Portland area, I found that it was best to list the area of town I was in. That kept out unwanted calls from areas I didn't service. It also had the side effect of drawing people in my area to call me rather than the other ads.
One last tip; I very rarely found it worth it to advertise in the Service Guide except during the spring time. The rest of the year I didn't usually get enough calls to warrant the advertising expense.