If you're not using a multi-introducer capable Tahoe installation, most are using killyourtv's introducer to connect to the grid so that would be a good choice to use as a primary introducer. Updating your Tahoe-LAFS installation is recommended.

If you're using the multi-introducer build, copy and paste the following into ~/.tahoe/introducers:

pb://c6w5ernw7y7rp3uwmdyu5clujyt2y4m4@w2zrwz5gplkkufix7cb4gmxfbrkwg2abnsgk62bm5iifzlahe7kq.b32.i2p/introducer
pb://exupps5kk3amc5iq4q6f5ahggkm4s5fl@oj7cffq5fnk46iw3i3h2sdgncxrqbxm7wh6i4h2cbpmqsydygkcq.b32.i2p/introducer
pb://md2tltfmdjvzptg4mznha5zktaxatpmz@5nrsgknvztikjxnpvidlokquojjlsudf7xlnrnyobj7e7trdmuta.b32.i2p/introducer
pb://fmcbgy7zd6ubrbphilmrlocvb7f327z5@gdr3tt5uewgnm7r7xn54k2qikf2kuwwegjjsnkz44pjticcacsua.b32.i2p/introducer
pb://tq7rx35yopkvodmsxkqra4qqkbho3yaa@6ga2r2h2fyq6tzcyh6bf3hpio3i7r4edadbq7l4wnh4y62taj6ia.b32.i2p/introducer
pb://cys5w43lvx3oi5lbgk6liet6rbguekuo@sagljtwlctcoktizkmyv3nyjsuygty6tpkn5riwxlruh3f2oze2q.b32.i2p/introducer
pb://r3bs6joub24gtsofe7ohnnjcnwfmo2jy@qaihdh5z7osn7tc3326ahv3z46badiuaulff43wchmap7skg7euq.b32.i2p/42mrbm7zxmjemz6hzejo3i7aunx4eoun

Active (as of 18-Sep-2014)

• killyourtv: pb://c6w5ernw7y7rp3uwmdyu5clujyt2y4m4@w2zrwz5gplkkufix7cb4gmxfbrkwg2abnsgk62bm5iifzlahe7kq.b32.i2p/introducer
• str4d: pb://exupps5kk3amc5iq4q6f5ahggkm4s5fl@oj7cffq5fnk46iw3i3h2sdgncxrqbxm7wh6i4h2cbpmqsydygkcq.b32.i2p/introducer
• COMiX: pb://md2tltfmdjvzptg4mznha5zktaxatpmz@5nrsgknvztikjxnpvidlokquojjlsudf7xlnrnyobj7e7trdmuta.b32.i2p/introducer
• Meeh: pb://fmcbgy7zd6ubrbphilmrlocvb7f327z5@gdr3tt5uewgnm7r7xn54k2qikf2kuwwegjjsnkz44pjticcacsua.b32.i2p/introducer
• uddh: pb://tq7rx35yopkvodmsxkqra4qqkbho3yaa@6ga2r2h2fyq6tzcyh6bf3hpio3i7r4edadbq7l4wnh4y62taj6ia.b32.i2p/introducer
• zoidberg: pb://cys5w43lvx3oi5lbgk6liet6rbguekuo@sagljtwlctcoktizkmyv3nyjsuygty6tpkn5riwxlruh3f2oze2q.b32.i2p/introducer
• weldok: pb://r3bs6joub24gtsofe7ohnnjcnwfmo2jy@qaihdh5z7osn7tc3326ahv3z46badiuaulff43wchmap7skg7euq.b32.i2p/42mrbm7zxmjemz6hzejo3i7aunx4eoun

Down (as of 03-Jun-2014)

• kiribati: pb://j3omzqrjgcsr7mwzrkekjxxyvt7jeah5@ysj3dhxrhav3aka25zr4vzrvckwqbmg4agpff4vmfsrmc4wtbbpa.b32.i2p/introducer
• LaughingBuddha: pb://t2brndkyv37mdwlnqyxs5duc3vbcazhm@xdeuqmm4nn2qd54wcfjwsvx2wcuvfmw5ghfjlentqvxprghpd3uq.b32.i2p/introducer
• kiribati: pb://j3omzqrjgcsr7mwzrkekjxxyvt7jeah5@yk3f75mhhllmhwksfecunudu4bxlowlb5tt4ajrqiieo4xfybnia.b32.i2p/introducer down 2012-02-14 due to lost destination key due to an I2P bug
• duck: pb://vysqjw7x7hfiuozjsggpd5lmyj35pggu@iyawu4w66gd2356vguey2veyn7jbpyzqgpmb74wd2gxzvkuzbxya.b32.i2p/introducer down 2011-10-22
• socrates: pb://yb6j4bb5r5r2gco5vrhbtv6pjwzkgzdi@fuynpbna7k4usuvlibzah2jn3fs2dxgovqeucyszghkqnaf6atwq.b32.i2p:0/introducer down 2011-07, probably not coming back
• nixer: pb://s66jgejlvgaw644o4mv4s5jn2uh4vx2x@dnty2phusg3kregmjw7cz3y7edmymmrfjmlfy7g43yql7wz4yv4q.b32.i2p/introducer
• i2system: pb://vj2ezdq6bu5uxbciqcoo65tay2nkfqdg@uzrf37svuqf37vd57jtwywddeufm4hkrsbtwkjde7kbtfqxx4t6q.b32.i2p/introducer
• Biotrophy: pb://kjmp37xarqa64mls4mugn5vigrf2z5xh@og6k64oxuvuym6lfjoys6vdxxg6c3kx76urmylbnicvpl4wmfbea.b32.i2p/introducer down 2012-05-18 due to lost node id
• Admin_LMH: pb://e7ycbg53a36nhmdq7dtewl25atyjq7ih@jbbvkooeqr7pid35jq2qfqczhvggj4vqred6snh3t6l4j7htdcfa.b32.i2p/introducer
• lesismor: pb://6y2vv5gnnd4lrw2mv4rehxfzapgdmebq@abaihqkysj6celuk6k6rmfnqjscf4uvl5nxrs4v7ykqjiarb4ydq.b32.i2p/introducer
• darrob: pb://cvgnicifwqidin2slcnzfml3zav62uwv@f7qcin3gsomzf4g7cowiyuucq3sxd2wxfa4jytvwykw3ldhjxaaq.b32.i2p/introducer
• Biotrophy: pb://dvx2hfl53drsxahkosuynvkgi3d75q3l@og6k64oxuvuym6lfjoys6vdxxg6c3kx76urmylbnicvpl4wmfbea.b32.i2p/introducer

A script to subscribe to introducers and news updates, intended to be run periodically via cron, is available at grid-updates and its use is very strongly recommended.