Ever thought of just using whatever app you like best and simply using Markdown or something to put the italics in?  I use WriteMonkey mostly on windows and it doesn't support any formatting, either, but it does support various forms of markup (like Markdown or Textile).  With it you just input a word that needs to be italicized like _this_ , and it can be output to Word or whatever through a filter that formats anything that's marked up like that.  I don't know Mac stuff, but lots of Mac guys (like http://www.practicallyefficient.com/ for example) are always using things like that and would probably make a good resource to setting something like that up for yourself.