Analyst firm Frank N. Magid Associates reports that roughly 12 percent of Americans have bought a virtual item at some point in the last 12 months, according to a study they made for virtual currency provider PlaySpan. With the virtual goods and currency market estimated to reach $1.8 billion this year, the Magid study offers some insight into exactly who’s doing the buying, and where.

Demographically, for example, while 15 percent of males aged 12-24 reported purchasing virtual goods, 15 percent of women between ages 35-44 did so, too. As Mike Vorhaus, president of Magid Advisors, put it, the boys are getting virtual swords for their MMORPGs, while the women are buying virtual flowers on Facebook. Vorhaus noted that categorization by ethnicity was also diverse, with Asian-Americans on the high end (16 percent), and the rest some 1-5 percent behind.

Segmenting that 12 percent according to consumers’ Internet activity and device ownership, social network gamers and iPhone owners are strongly represented (27 and 28 percent, respectively); PC and handheld console gamers were almost as likely to buy virtual items (between 19 and 22 percent.) However, active console gamers lag just a bit behind those segments.

Unsurprisingly, the most significant variable in purchase rate is virtual world usage: Nearly half of the respondents who report being active MMO participants are also virtual item consumers.

Meanwhile, Eric Hartness, chief marketing officer at PlaySpan, said that he expects that by this time next year, that 12 percent figure will rise to 15-18 percent.