Since she’s on a language study trip, if you can’t think of anything to say, just say “Ok, now let’s practise English! :D” – that should buy you some time ;)
As for serious suggestions, it might be better going to a bigger Japanese learning forum with more people that are more experienced; TextFugu’s ok and all, but there really aren’t that many people here that are anywhere near fluent. Like in my case, I’m just like you: “My reading and writing skills are my strong point, but I have practically no conversational experience.”; hell, even in English my small talk skills are no good :P
These might be good places to ask (can’t say for sure as I’ve not used them):
http://www.reddit.com/r/learnjapanese
http://japanese.stackexchange.com/