I couldn't find anything on Rick Santorum's official website on immigration (neither could NumbersUSA). The following is taken from Fox News Latino
Santorum’s immigration policy falls in line with the general, hard-line stance held by most of the GOP hopefuls on the issue.
The son of Italian immigrants, he strongly opposes amnesty for
undocumented immigrants, believes building more fencing along the border
is an important part of the immigration issue, and also supports making
English the official national language.
Santorum voted against establishing a Guest Worker Program with a
path to citizenship for undocumented immigrants in 2006, and is also
strongly against in-state tuition for undocumented immigrants. He made
this clear in the September Fox News – Google Debate in which he
attacked Texas Gov. Rick Perry for allowing undocumented immigrants in
Texas the right to in-state tuition costs at state schools.
“What Gov. Perry's done is he provided in-state tuition for illegal
immigrants. Maybe that was an attempt to attract the illegal vote--I
mean, the Latino voters. But you attract Latino voters by talking about
the importance of immigration,” Santorum said.
Santorum is a strong supporter of a fence along the U.S.-Mexico
border in the hopes that it will stem the tide of undocumented
immigrants entering the country. “What I would say is that first, we
build the fence. Number two, we enforce the law, and that is that we
don't allow people who are in this country to work here illegally,”
Santorum said during an interview with Greta Van Susteren on Fox News
Channel’s “On The Record. “And when we do find people here illegally,
and we go through the process of deportation.”
In recent debates Santorum has gone after Texas Gov. Rick Perry for
being “soft on immigration” and opposed Perry’s resistance to a border
fence. “What we have is a problem of an unsecure border,” Sanotrum said
during the TEA Part debate.“Unlike Governor Perry, I believe we need to
build more fence…I believe that we need to secure the border using
technology and more personnel. And until we build that border, we
should neither have storm troopers come in and throw people out of the
country nor should we provide amnesty.”