Help with connecting rack and fenders

[CyclaSutra]

Hey! I hope some of you gals have had this trouble before... I ordered an awesome rack and fenders, but can't ask my LBS for help putting them on because I didn't order from them. The rack says it's supposed to screw into the "threaded seat-stay bosses" which I don't have on my old mountain bike turned commuter.

I'm having a helluva time attaching these pix for some reason. I just hope somebody else has had this problem and knows what to do about it!

I'm trying to figure out if I should go to the hardware store and get a bolt to go between my rear triangle tube and the seat tube, or whether I should just try to zip tie it ...

and on the right side of my suspension fork, no eye to hold the fender doodad... so should I just zip tie/duct tape it all together and hope for the best ??? Just seems like my 6-year-old race-worthy aluminum hardtail wasn't made for this attaching stuff business.