Hunting down Chrollo x Kurapika fics is one of my little weekend rituals—tea, headphones, and an endless scroll. The best place I usually start is Archive of Our Own; its tagging system is brilliant for specific pairings, so try tags like "Chrollo Lucilfer/Kurapika" or simply "Chrollo/Kurapika" and then filter by rating if you want SFW or mature content. FanFiction.net and Wattpad also have lots of entries, though their tag systems can be messier, so search with character names and add tropes like "angst" or "cozy" to narrow things down.
If you prefer community recs, I lurk on subreddits related to 'Hunter x Hunter' and on Tumblr blogs that curate pairings. Discord servers for 'Hunter x Hunter' often have fanfiction channels where people post fresh works and link to archives. Pro tip: use Google site searches like site:archiveofourown.org "Kurapika" "Chrollo" if you want precision. Always check tags and warnings before diving in—some fics can be very dark. Personally, I start with AO3 for mature, well-tagged stories, then hop to Wattpad for fluff and to Tumblr for one-shots and art crossovers.