I'll throw in a couple tidbits:
An H-1B visa isn't citizenship, nor is it permanent residence. It allows someone to stay in the US and work for a US employer (and hold no other jobs at the same time). In general, H1 and L1 visas are among the only way for people from outside of the NAFTA trade zone to seek employment-based entry into the US. There are other visas like O visas (typically used by people with extraordinary talents) or refugee visas and the like, but those are generally not applicable to your candidates.
If you want to hire Canadian (or possibly Mexican) citizens, they do not need a visa to work for you. You can instead sponsor them to obtain a TN (NAFTA) work permit. These permits are somewhat easier to obtain because there is no lottery, no cap, and no window of opportunity effect (The H-1B visa cap is generally filled within the first moments of April 1st of every year). Since a TN work permit is not a visa, it doesn't lead to permanent residence. It can be renewed virtually indefinitely, however.
Hiring a legal firm to handle paperwork of dealing with USCIS and other entities involved in bringing a person into the US is pretty much unavoidable, though not unheard of.