Depends on what you want-
If you want a carbine, the most commonly found examples are German k98s,Czech vz-24s, Swedish M38s, Yugo24/47, 24/52s and m48s, Spanish carbiines are still fairly common as well.There are probably hundreds of other variants, but you won't commonly see them.
Yugo rifles are appealing because they can be had for cheap and in relatively good condition (I've bought a few unissued ones a few years ago), but their quality is pretty low- most will shoot good, but a lot of them are plagued with problems.
I highly reccommend German, Czech, and Swedish rifles, you'll pay a bit of a premium for these, but you get a lot more than you pay for.
If you want a full length rifle, turks, swede M96s, czech vz-22 and 98/29s can be found. All are good, but Turks have usually had a lot more hard use and a lot less maintenance than the rest.
My top two reccomendations are:
http://samcoglobal.com/rifles.html#m9829
I have one of these in VG condition, its an outstanding rifle. The only 8mm I have that will outshoot it is a vz-22, but those are getting hard to find.
for acarbine:
http://samcoglobal.com/rifles.html#m98kmc I have one of these in special select condition- its a brand new rifle. Its a little rough in the craftsmanship department, and the trigger is somewhat gritty, but its still head and shoulders better than a Yugo.