As web designer, what I always do is dige for similar fonts, and put in the css font-family: font1, font2, font3 … But checking how it’s seen in severallinuxes, mac, and win. I know Arial wont display inm several systems, but know fonts that will playe well at least with my design as well.
If you go to Wikipedia and dig for a font, is usual to read the font from which it came, or which it has evolved to, which are similar… that unless you already know which are similar.
I use a lot Arial, Bitstream Vera Sans, helvetica, Verdana, Tahoma, Freesans, Lucida Grande and so on.
These have proved to be very helpful in one or other situation, when trying to do a similar design for several browsers/oses. In my experience, I mean. The key is not only knowing the similar ones, but also the order: if it does not find a font it goes obviously to the following, so you can give it a thought on how you make each your css classes knowing that.