Peter, you're going to want to be careful of these links, and keep an eye out for any more of them.
The sites those links are coming from have been very severely hacked. Someone has hacked into those sites and hidden hundred of spam links on their pages. (You'll only see the links if you look in the source code of the pages.) At least some of those links pointed to pages on your site.
Why would they point links to your site? The most common reason is that they are trying to create a "link wheel". That's where they point a bunch of links at another page to try to give it ranking power. Then they insert more spam links on that second page, hoping that the increased ranking power will make those links more powerful. It's totally a spam tactic and doesn't really work anymore, but it can still be very damaging to a site that's been hacked to do it.
So what should you do? The very first thing you must do is conduct a review of your own site's pages to be CERTAIN you haven't been hacked and had links inserted on your site. I've done a quick review, and it doesn't appear that you have any issues with this, but you'll want to do a deeper check just to be certain.
Second, you need to decide if these types of links can hurt you. Because they are crap links from unrelated sites, they will look very spammy. Having too many of these crappy incoming links is what can trigger a Penguin algorithm penalty. This is only likely to happen if those crappy links form a significant percentage of your incoming links.
What I would do is immediately begin keeping a spreadsheet listing any and all of those crappy incoming links you detect. If there are only a few of them (less than 5% of your total incoming links), then I'd just keep adding to the list as you find them, and make a notation that they're coming from hacked sites. If you continue to see new crap links being created, keep adding them to the spreadsheet.
Once they get close to totaling 5% of your overall incoming links, I'd prepare a disavow file and submit them using Google and Bing's disavow tools. The point here is - you don't want to submit a new disavow request every time you find a few links. But if the number of bad links is starting to pile up, you want to inform the search engines that you know about them, know they are crap links, and are not responsible for creating them.
Some people will tell you that you shouldn't submit disavow requests unless you have received a penalty notification. My position on this from experience is that it is VERY hard to get a penalty lifted once it's been applied. Much better to try to avoid the problem in the first place. But as I say - you don't want to be sending a new disavow list every time a few bad links show up. That could be counterproductive too.
As a last effort, I'd also take an hour or so to send emails to the hacked sites that are sending you the bad links. Politely and helpfully inform them that they have been hacked and are being used for spam attacks. Let them know that their security problem is not only hurting many other sites, but that it is likely badly damaging their own sites' rankings as well. Some will be appreciative and try to fix the issue, some will just ignore you. But if you should ever receive a penalty, you will immediately be able to show Google your list of monitored bad links and proof that you tried to contact the offending sites to get the links removed. These are the two critical components to being able to get a penalty lifted quickly.
Bottom line - I don't mean to alarm you here, but you need to be proactive to ensure you are protected. As long as you're sure your own site is clean, and the total number of crap links isn't too high, there isn't much to worry about. And if the number of crap links starts to escalate, your monitoring and records will put you in a position to easily submit a list of all of them through the disavow tool.
I know that's a to digest, but since you indicated you're not yet well-seasoned in this kind of thing, I wanted to try to be thorough. If you still have questions, be sure to ask!!
Paul