Most of the Japanese songs I'e heard happen to be OST's from dramas..
Taiyoni Warae - Anly (Siren) https://youtu.be/hZj7Iykh7lo
Realize- Melody (Dragon Zakura) https://youtu.be/AgjtmlsVhcM
Savage Heaven - bump.y (Limit) https://youtu.be/T0DxnmH95mo
Seishun Amigo - Shuji to Akira (Nobuta wo Produce) https://youtu.be/41nWPwshqKo
Chippoke na Yuki - Funky Monkey Babys (Asuko March) https://youtu.be/FKXBSuN-nQo
Ikenai Taiyou - Orange Range (Hanazakari no Kimitachi e 2007) https://youtu.be/Sn9-aNG66GI
Peach- Ai Otsuka (Hana Kimi 2007) https://youtu.be/kjBG7nR7GuU
Ichibu to Zenbu - B'z (Buzzer Beat) https://youtu.be/3-lnzdy2XIo/ https://youtu.be/7XtfVYPghhs
Forever - Takashi Sorimachi (Beach Boys) https://youtu.be/DAHPp-u3nDY (has scenes from the drama)
Kage - Shibasaki Kou (Byakuyako) https://youtu.be/uZVHnZQLUlY (has scenes from the drama)
Ride on Time - Tatsuro Yamashita (Good Luck) https://youtu.be/voCfulkALl4
Kimi ni Todoke - Tomofumi Tanizawa (I think this song is in the anime) https://youtu.be/9aBiHYT_8UI
Poison - Takashi Sorimachi (GTO 1998) https://youtu.be/XiRKD_1S4e0
Sorafune - Tokio (My Boss, My Hero) https://youtu.be/DzJhIInNi_4
Diamond Dust - Kyosuke Himuro (Ice World) https://youtu.be/LNSwpRSmjYQ (has scenes from the drama)
Everybody Go - Kis-My-Ft2 (Ikemen Desu Ne) https://youtu.be/OnAVILTiKl8
Akuma no Koi - Nakayama Yuma with B.I. Shadow (Koishite Akuma) https://youtu.be/FNadJPofEYs
Prisoner of Love- Hikaru Utada (Last Friends) https://youtu.be/6bDyqwwH4Xs
La la la love song- Toshinobu Kuboto (Long Vacation) https://youtu.be/HiNQeQQJWgw (has scenes from the drama)/ https://youtu.be/TGQuCyLvay8
Every Hero - Kaho (Miss Pilot) https://youtu.be/XcNMdmYEXf4
Voice - AI (Yakou Kanransha) https://youtu.be/dDXPP-ipMeQ
Make my day - Sexy Zone (The Black Devil and the white Prince movie) https://youtu.be/H0_FnOunZms/ https://youtu.be/iUHTul54TLM
And also..
Senbonzakura - Wakkagi band https://youtu.be/K_xTet06SUo
Yuukaku Disco - Shinobu Kawashima https://youtu.be/CYwql2EUQlk
Also songs by Arashi (Beautiful days, Breathless etc) , Tomohisa Yamashita (Nocturnal, Loveless..)