Hi Andres,
In pro version of soapUI there's a feature you're asking for - called
DataSource Step.
You could achieve something similar using the free version of soapUI with a 3rd party library like
JExcel to programmaticaly import data using Groovy script.
However, as
previously answered to a similar question, giving you further details on how to go around pro version features would be out of scope of free support.
I hope you understand.

Cheers!
/Nenad Nikolic a.k.a. Shonzilla