Sometimes it really tough to acquire info like that. You might already know about what I'm going to write, but it may help others.
Using your example 1HU3058-0AF01-0ZZ9-Z...
First, you throw it into Google as is. As you've discovered, you get lots of hits about repair and sales. Not what you're looking for, but when you look at a few of those pages, you discover that the part number is for a Siemens DC servo motor. OK, so you already knew that, but lets say you didn't.
We now know that it's a Siemens motor, so we go to their website. They have a search box, so we throw your part number in there. Zero results. Wow, Siemens made it, so you'd think THEY would know more than Google. OK, while we're at the Siemens site, let's drill down to servo motors. Notice the naming conventions they use for their current motors; 1FT7, 1FK7. We can make an educated guess that your part number is probably for a 1HU3 series motor. A quick Google search for 'Siemens 1HU3' confirms this is probably true.
Let's try typing 1HU3 in the search box at Siemens. Hey, now we got 12 results. You may find what you need, assuming their site search works well. If it doesn't, or if they didn't HAVE a search box, we can just use Google. If you use Google's 'advanced search' you can search for 1HU3 ONLY at the siemens.com domain. This produces a search for "1HU3" with "site:siemens.com" after it. Hey, Google found more results than Siemens!
In this specific case, the first PDF seems like the only 'useful' information (and you may need to translate some of the terms), but it may be of some help...
-Eric
