Data Merge, third party plug-ins and XML all need some kind of structure to a document before anything can really be automated. The samples, while they have a content structure (that is, a picture has a description, price and name) it doesn't have a predetermined position on the page.
Assuming the excel file also has the picture name in one of the fields, data merge could be used to call in all the data and merged via multiple record layout into a new indesign file, but it wouldn't appear as the final layouts above... instead the file would appear as a grid. From here, the pictures and their captions need to be moved to their appropriate positions.
I've been umming and ahhing over what to write in the post but ultimately there is no turn-key solution. The best I can think of would still involve running a script on each page and then processing the result of that manually. Automated catalogues are ideal for the likes of phone directories, parts catalogues or school yearbook pictures. this catalogue is outside of those specs and I can't see a way of automating this... as a turn-key solution. I would be interested to see what other posters have to say but I think this is a bridge too far to automate.
In terms of what may make the job easier, try these two links though:
http://ajarproductions.com/blog/2008/11/28/merge-textframes-extension-for-adobe-indesign/ (a script for merging loose text frames into one big textframe)
http://tomaxxi.com/2011/04/mastering-live-captions/ (for using the captions feature to do lots of the hard work of presenting the data under a picture)
Thought about it.
The whole formatting for a productdescription can be done with one paragraphstyle including some nested grepstyles.
A tagged text line will be as simple as:
<ANSI-WIN> <-Encoding <vsn:7.5> <-Version <pstyle:Description>9.<0x2005>123456 Name, with several features<0x2002><0x20AC><0x200A>99,-
Let's expect a row in the excelfile like:
Number ArticleNumber Name description Price
So exporting the excelfile to *.csv, adding taggs needed to create tagged text files from each row by scripting
Now those tagged text files can be imported -> option: linked
This may be done scripted by following some rules ...
Hope this'll help