Modern military tech is obviously extremely classified and you won't be able to find many pictures. Here's a little bit that is public knowledge though:

KH (Keyhole) Series – Reconnaissance (USA)
>KH-11 (“Crystal”/“Kennan”):
>Launched since the 1970s; still in use in upgraded forms.
>Rumored to resemble the Hubble Space Telescope, as both were built by Lockheed and have similar optical systems.
>Approximate size: ~15 meters long, with large aperture optical lenses.
>No official photos, but artistic renders and declassified diagrams show a long cylindrical body with solar panels.

Lacrosse / Onyx – Radar Imaging (USA)
>Uses synthetic aperture radar to see through clouds and darkness.
>Declassified photos show a boxy satellite with large radar panels.
>Likely ~15 tons with large side-facing antennas.

Mentor (Advanced Orion) – Signals Intelligence (USA)
>Enormous geostationary SIGINT satellites.
>Estimated to be the largest non-space station satellites ever built (~20,000 kg).
>Believed to have huge dish antennas for intercepting radio and satellite communications.