error, string or binary data would be truncated when trying to insert

I am running data.bat file with the following lines:

Rem Tis batch file will populate tables

cd\program files\Microsoft SQL Server\MSSQL
osql -U sa -P Password -d MyBusiness -i c:\data.sql

The contents of the data.sql file is:

   insert Customers
            (CustomerID, CompanyName, Phone)
             Values('101','Southwinds','19126602729')

There are 8 more similar lines for adding records.

When I run this with start > run > cmd > c:\data.bat, I get this error message:

1>2>3>4>5>....<1 row affected>
Msg 8152, Level 16, State 4, Server SP1001, Line 1
string or binary data would be truncated.

<1 row affected>

<1 row affected>

<1 row affected>

<1 row affected>

<1 row affected>

<1 row affected>

Also, I am a newbie obviously, but what do Level #, and state # mean, and how do I look up error messages such as the one above: 8152?