Here are some useful websites that I recommend:

English:

salafipublications.com | Birmingham UK

salafisounds.com | Birmingham UK

ah-sp.com | Abu Hakeem Bilal Davis, Birmingham

abukhadeejah.com | Abu Khadeejah, Birmingham

salafiEbooks.com | Abu Iyaad Amjad Rafiq UK

salafibookstore.com | UK

facebook.com/SalafiPubs/ | Facebook Salafi Publications

facebook.com/AbuKhadeejahSP | Facebook Abu Khadeejah

islamagainstextremism.com | Counter-Extremism, SP

aboutatheism.net | Combating the falsehood of Atheism, SP

manhaj.com | Methodology of the Salaf, SP

SalafiMasjid.com | Wright Street, Birmingham UK

dajjaal.com | Liars and False Prophets, SP

shia.bs | Shi’ite beliefs, SP

ProphetMuhammad.name | About the Messenger (salallāhu ‘alaihi wasallam), SP

islamJesus.ws | About Jesus (peace be upon him), SP

salaf.com | SP, UK

aqidah.com | SP, UK

themadkhalis.com | SP, UK

asharis.com | SP, UK

islaam.ca | Toronto Canada

alBaseerah.com | Bradford UK

dusunnah.com | Shepherd’s Bush, London UK

cardiffdawah.co.uk | Cardiff, Wales UK

salaficentre.com | Manchester, UK

markazmuaadh.com | Slough UK

Troid.ca | Toronto, Canada

sunnahpublishing.net | Michigan USA

germantownmasjid.com | Philadelphia USA

rahmaniyyahpublishing.wordpress.com | Abul-Hasan Malik, New Jersey, USA

bakkah.net | Moosā Richardson

Arabic:

alfawzan.af.org.sa | Shaikh al-Fawzan, Riyadh KSA

binbaz.org.sa | Shaikh Ibn Baz, KSA

ibnothaimeen.com | Shaikh Ibn Uthaimeen, KSA

rabee.net | Shaikh Rabee ibn Hadi, Madinah, KSA

njza.net | Shaikh Zayd al-Madkhali, Samitah, KSA

elbukhari.com | Shaikh Abdullah al-Bukhari, KSA

ar.miraath.net | Jeddah, KSA