There are now a dozen courses in the country, nearly all of which are within a one-hour drive of Ljubljana - including the nine-hole Trnovo course located just south of the city centre. Trnovo is also conveniently the only course in the country at which non-licensed golfers can officially play, although in practise many courses will waive this requirement for foreigners who can persuasively attest to their skills (and pay the green fee).
A few minutes' drive northwest of Ljubljana, in the settlement of Smlednik, you can find the Diners Club course, which as could be assumed from the name boasts a first-class clubhouse and restaurant, while 20km or so to the northeast the Arboretum course is perhaps our favourite place to tee off in Slovenia, offering a winning combination of reasonable greens fees, a lively clubhouse and incredible views of the nearby Alps, in addition to the proximity to where we live. Meanwhile, the most storied links in the country are located near the fairytale alpine town of Bled, and offer truly breathtaking views of the surrounding mountains during your round.
For any general golf-related queries the best people to contact are probably the friendly folks at the Professional Golfers' Association of Slovenia.