If I am delinquent on a loan payment, can they legally garnish my wages through the court or is this a standard tactic used by companies to obtain payment?

Yes they can...

I'm sure they have contacted you about it many times, when companies get to the wit's end, they take extreme measures. This being one. If it's a bank loan then yes they can. It sucks. But ignoring these things makes them worse. If you were not able to pay it you should have contacted them and told them so. You could have worked out a smaller payment system. At least they would have known the situation and possibly been more lienent with you.

Before they can garnish your wages, they have to sue you and obtain a judgement against you. Also the type of loan has a bearing on this. Once they get a judgement, then a writ of garnishment is one of the tools they can use.