Some useful links to other pages that show Nepticuloidea or other leafmining Lepidoptera
Global:
Catalogue of life Nepticuloidea http://www.catalogueoflife.org/col/details/database/id/172
Global taxonomic database of Gracillariidae http://www.gracillariidae.net/
Europe:
Leafminers and plant galls of Europe http://www.bladmineerders.nl/
This site is organised by hostplant genus, with keys to the leafmines.
Identification of Central European Lepidoptera, Nepticulidae http://www.lepiforum.de/lepiwiki.pl?Fotouebersicht_Nepticulini_Gesamt_1 in German/auf Deutsch
Very good for most Lepidoptera.
North America:
BugGuide http://bugguide.net/node/view/99735/bgpage
BugGuide has more photos and often more recent identifications than the next site.
Moths photographers group http://mothphotographersgroup.msstate.edu/species.php?hodges=37 This shows the first species, scroll further by clicking "Next Plate"
Mainly photos of adults, for Nepticuloidea still rather poor
BugTracks, blog by Charley Eiseman about all sorts of miners and alike https://bugtracks.wordpress.com/
Nice blog with many new discoveries.