You should try a place called the Seafood Depot on Aviva Park Drive off of Weston Rd, north of Steeles(across from the Toronto Star office). They sell lots of neat things at good prices that you could wrap yourself. I haev gone there for favors from my brother's wedding shower and for my parents anniversary party. You should make this your last stop as they do sell fish as well, and you are guaranteed to come out smelling like fish. I hope this helps.
They will give you as many cards as you need. I ordered an extra 25 just in case. Some guests wanted an extra and I had family that couldn't come who I wanted to give these to as they had sent me a gift as well and I just put it in the envelope with the thank you card.
I just got married in May. I bought 2 pounds of bulk wildflower seed for 150 guests and filled small plastic bags with the seed so that it is not spill everywhere then put the bags in flower boxes. I only had 10 boxes left because guest were taking the seeds out of the boxes and leaving the boxes behind. I found the favors at http://www.favorideas.com/shopping/prod/GS67227.htm Hope this helps.
What month is your wedding and do you want a favor that matches the season? As a generic idea: we bought lace boxes - since lace was a theme we carried throughout our wedding - and filled them with pastel candy-covered chocolates from our local bulk grocer. They doubled as place card settings and we printed special thank-you messages on them to our guests. We tied them with ribbon in our wedding colors, also.
theknot.com has a wedding shop with favor ideas too.