Some writers use the terms evaluation and feedback interchangeably. This could be the reason you haven't found much on the web under evaluation.
If you're really interested in the topic, there is a book on evaluating in the Richmond Handbooks for Teachers series.
Here are some ideas for evaluating students' progress:
You can give a quick quiz at the end of the lesson to review what was worked on in that lesson or over the last few lessons. Probably more useful for grammar and vocabulary.
You can do regular short progress tests. Let students know that you're assessing what areas need to be worked on, so they don't see the test as contributing to a final pass mark.
Many coursebooks incorporate test materials. Make sure you use progress tests and not placement tests.
For speaking tests, you can set up group activities. You can score them on all or some of the following: participation, fluency, accuracy, pronunciation, vocabulary etc.
To assess listening, it's interesting to re-do a listening activity from earlier in the course and to compare how they performed both times. If a student does less well, it could just be due to tiredness etc, so don't take it as meaning a backward step.
For evaluating your teaching you could:
Focus on one aspect of teaching and after a lesson write down if it went well or not, along with the reasons. You can then decide which aspects to incorporate into your repertoire and which need improvement.
Often the initial reaction on finishing a class is that it was all good or all bad. It's a good idea to write down a few ideas immediately after the class and again the following day.
If possible, you can video yourself teaching. This will give you a lot of material to work on. Tape recording is possible if you don't have access to a video recorder, but it's more dense to work through and you don't pick up on a lot of the interaction.
You can also ask a colleague, whose opinion you respect, to come in and observe you. You can ask this person to give you global comments or to focus on one area.
Encourage your students to evaluate your lessons. If something's going well, they'll probably let you know. They may also have a different vision to you. Not all people find it easy to give feedback to their teacher. So start small.
At the end of a lesson, you could ask:
what did you like most / least? (written or oral)
what have you learnt today?
At regular intervals, ask them to write down activities they would like more or less of.
Once or twice during the course, you could have "tutorials". Set up an activity where students can work independently, then speak to each of them individually. You can then discuss how they feel about their progress and they can give you feedback on what they think of the classes.
Finally, I think it shows that you are really committed to helping your students and wish you good luck with this.