There are quite a few Arends on the U. of St. Thomas index and Wagener (note spelling) is fairly common also. Did either of them have any siblings?I would get their names also and look at what records they have.Do you have the church record for the marriage?Sometimes the priest records the place of birth which is what happened with my ggrandfather's death record-had parents' names, including maiden of mother, birth date and village name in Luxembourg otherwise I would be looking all over Germany for them because my Dad said he was all German or Prussian.
Take a look at Therese Becker's website for some general information to help you get started with the Lux. records.
If you are close to the St. Paul, Minnesota area, the U. of St. Thomas has many of the LDS (Mormon church) microfilms of the Luxembourg records as well as a large collection of books relating to Lux. If you can visit there, call first to let them know that you are coming.
The Mormon Church has genealogical guides in several languages. If you are going to pursue the Lux records, I would get French, Latin and German. The German will help you with most of the Lux records. I would also get the guide to the French calendar. Records in the late 1790s (?) and early 1800s use the French calendar and may be in French. Lots of fun trying to figure out what the date is.
If this is the first time that you have posted to this board, you might want to go back over previous postings. There are some very interesting links and also general information that can help you in your search.
Once you find out where they lived, you might want to view the villages as they are now.
Recently the Mormon Church has put the images online for many of the Luxembourg records. They are not indexed. Go to the following and click on the “Search or browse our records collection”. Click on Europe and then scroll down to Luxembourg and select “Luxembourg Civil Registration 1793-1923”.
You do not have to go through every last page. There are 10 year indexes that are called Decennales. They are generally in alphabetical order. Marriages are in order by the groom's surname. When you get to the individual birth, death and marriage records most of them have an index at the year of the year. I didn't know this when I first started and was going through every page. Most of the time I have found the death records for women under their maiden names but not always.
I did not re-check the links.Let me know if they are broken or whatever it is called.Good Luck.