WREX-TV in Rockford, Ill., reported Palin rolled up to the Reagan home in her "One Nation" tour bus shortly after noon. She signed autographs, shook hands and posed for photos, supporters who greeted her told the TV station.
Palin was accompanied by her husband Todd and daughter Piper,
Rockford's WIFR-TV reported the former Alaska governor and 2008 GOP vice presidential candidate, who is contemplating a run for her party's presidential nomination in 2012, kept a lid on her surprise visit to Dixon for Ronald Reagan Trails Days. To minimize media coverage, only the executive director was privy to Palin's plan to show up at the museum celebrating the life of the former Republican president, the TV station said.
Palin told an Iowa crowd Friday she hasn't decided whether she is running for president.
"I think there is plenty of time to jump in the race," she said. "Watching the whole process over the last year certainly shows me that, yes, there is plenty of room for more people."
After the 2008 election in which Democrat Barack Obama defeated Sen. John McCain, R-Ariz., Palin wrote a book and became a commentator on the conservative Fox TV news channel. She also hosted a TV series about life in Alaska.
At her Iowa appearance, Palin denied she was using her celebrity status to detract from other Republican presidential hopefuls.
"I don't think I'm stealing any spotlights," she said. "We're very thankful to have been invited by friends, and I'm glad we could make it."