I made some last year and just had some for diner last night and it was amazing. One of those "Wow, I made this and its that good" moments.
I dont know the exact ratio's I used. I took a recipe that came with my Cabelas meat grinder and modified it. The ratios can be adjusted to suit your taste.
~ 5 lbs of ground venison
~ A few apples (cored and skinned)
~ 1 lb of bacon
Salt and pepper
I think i put in a little of some other spice ( I will try to look it up and edit this post)
I ran the venison though the meat grinder once on a course setting. Mixed in the the salt, pepper, and spices and then ran the venison though again (course setting), mixing in and grinding the apples and bacon with the venison. The bacon fat does not treat the grinder nicely and clogs up the exit plate. I had to take this apart and clean it out a few times.
My wife and I think it needs a little "bite" to it. I am not sure what spice would do this but plan on experimenting with it if I get another deer this year.
Also I picked up a kit at Walmart last night that has the spices to make breakfast sausage and natural casing. I haven't made tube sausage yet but hope to try that out.